Code-coverage self-contained machinery, phase 1

[hemidactylus]

Phase 1 means that this PR refactors the whole unit+integration test workflows in the following way:

• usage of pytest-cov to generate coverage data in all integration tests + one unit test (py3.11 at the moment)
• those partial pieces of data are each stored as artifacts
• the test workflows are now orchestrated by a workflow that waits for them, downloads these files and combines them into the "full .coverage" file
• it then creates a HTML report (zipped and available for later inspection); prints the coverage report as PR comment, if this is a PR
• it uploads the JSON report if this is a push to main.

Phase 2 will add a step, in PRs, that compares the currently-generated JSON report to that of the base commit (i.e. on main) to post a comment with delta information.

[github-actions]

Coverage report

for commit: e8bf5e201a47d768befc1fe1b82f1fd94e38b11f.
download detailed report here.

Name                                                   Stmts   Miss  Cover
--------------------------------------------------------------------------
astrapy/__init__.py                                       26     10    62%
astrapy/admin/__init__.py                                  3      0   100%
astrapy/admin/admin.py                                   762    361    53%
astrapy/admin/endpoints.py                                36      3    92%
astrapy/api_options.py                                     3      0   100%
astrapy/authentication.py                                138     24    83%
astrapy/client.py                                         67     11    84%
astrapy/collection.py                                      2      0   100%
astrapy/constants.py                                      72      6    92%
astrapy/cursors.py                                         7      0   100%
astrapy/data/__init__.py                                   0      0   100%
astrapy/data/collection.py                               754     57    92%
astrapy/data/cursors/__init__.py                           1      0   100%
astrapy/data/cursors/cursor.py                            92      3    97%
astrapy/data/cursors/farr_cursor.py                      338     11    97%
astrapy/data/cursors/find_cursor.py                      630     30    95%
astrapy/data/cursors/pagination.py                        21      4    81%
astrapy/data/cursors/query_engine.py                     211     16    92%
astrapy/data/cursors/reranked_result.py                    8      0   100%
astrapy/data/database.py                                 657     75    89%
astrapy/data/info/collection_descriptor.py               197     33    83%
astrapy/data/info/database_info.py                       104     11    89%
astrapy/data/info/reranking.py                           122     18    85%
astrapy/data/info/table_descriptor/table_altering.py     114     11    90%
astrapy/data/info/table_descriptor/table_columns.py      204     17    92%
astrapy/data/info/table_descriptor/table_creation.py      49      2    96%
astrapy/data/info/table_descriptor/table_indexes.py      233     30    87%
astrapy/data/info/table_descriptor/table_listing.py       49      6    88%
astrapy/data/info/table_descriptor/type_altering.py       85      7    92%
astrapy/data/info/table_descriptor/type_creation.py       32      2    94%
astrapy/data/info/table_descriptor/type_listing.py        39      4    90%
astrapy/data/info/vectorize.py                           131     14    89%
astrapy/data/table.py                                    737     65    91%
astrapy/data/utils/__init__.py                             0      0   100%
astrapy/data/utils/collection_converters.py               80      4    95%
astrapy/data/utils/distinct_extractors.py                103      1    99%
astrapy/data/utils/extended_json_converters.py            28      0   100%
astrapy/data/utils/table_converters.py                   411     20    95%
astrapy/data/utils/table_types.py                         36      0   100%
astrapy/data/utils/vector_coercion.py                     12      0   100%
astrapy/data_types/__init__.py                            10      0   100%
astrapy/data_types/data_api_date.py                       89      6    93%
astrapy/data_types/data_api_dict_udt.py                    9      1    89%
astrapy/data_types/data_api_duration.py                   55      5    91%
astrapy/data_types/data_api_map.py                        58      8    86%
astrapy/data_types/data_api_set.py                        89     23    74%
astrapy/data_types/data_api_time.py                       98      7    93%
astrapy/data_types/data_api_timestamp.py                  98     11    89%
astrapy/data_types/data_api_vector.py                     43      7    84%
astrapy/database.py                                        2      0   100%
astrapy/event_observers/__init__.py                        5      0   100%
astrapy/event_observers/context_managers.py               26      2    92%
astrapy/event_observers/events.py                         50      0   100%
astrapy/event_observers/observers.py                      29      1    97%
astrapy/exceptions/__init__.py                           108     19    82%
astrapy/exceptions/collection_exceptions.py               39     11    72%
astrapy/exceptions/data_api_exceptions.py                 84      1    99%
astrapy/exceptions/devops_api_exceptions.py               79      6    92%
astrapy/exceptions/error_descriptors.py                   53      3    94%
astrapy/exceptions/table_exceptions.py                    26      8    69%
astrapy/exceptions/utils.py                               53     11    79%
astrapy/ids.py                                             5      0   100%
astrapy/info.py                                           15      0   100%
astrapy/repl.py                                           76     76     0%
astrapy/results.py                                        50     16    68%
astrapy/settings/__init__.py                               0      0   100%
astrapy/settings/defaults.py                              57      0   100%
astrapy/settings/error_messages.py                         2      0   100%
astrapy/table.py                                           2      0   100%
astrapy/utils/__init__.py                                  0      0   100%
astrapy/utils/api_commander.py                           226     18    92%
astrapy/utils/api_options.py                             202     20    90%
astrapy/utils/date_utils.py                               80      2    98%
astrapy/utils/document_paths.py                           45      0   100%
astrapy/utils/duration_c_utils.py                         66      2    97%
astrapy/utils/duration_std_utils.py                       92      7    92%
astrapy/utils/meta.py                                     36      8    78%
astrapy/utils/parsing.py                                   7      1    86%
astrapy/utils/request_tools.py                            32      0   100%
astrapy/utils/str_enum.py                                 32      1    97%
astrapy/utils/unset.py                                    10      1    90%
astrapy/utils/user_agents.py                              18      3    83%
--------------------------------------------------------------------------
TOTAL                                                   8750   1141    87%