ESMValTool ozone diagnostics

[axel-lauer]

Description

ESMValTool ozone diagnostics. This includes the following five subdiagnostics:

• ozone-lat-time: zonal mean total column ozone (time vs. latitude)
• ozone-sh-oct: time series of total column ozone in October averaged over SH polar latitudes (60S-85S)
• ozone-nh-mar: time series of total column ozone in March averaged over NH polar latitudes (60N-80N)
• ozone-zonal: zonal mean profiles of stratospheric ozone (latitude vs. air pressure)
• ozone-annual-cycle: annual cycle of zonal mean total column ozone (month vs. latitude)

As reference data, obs4MIPs C3S-GTO-ECV-9-0 total column ozone and ESACCI-OZONE (SAGE-OMPS) ozone are used. ESACCI-OZONE data are not part of obs4MIPs or obs4REF yet.

This is as far as I can get. I am not able to add tests, etc. For this I need assistance from more experienced REF contributors.

Checklist

Please confirm that this pull request has done the following:

• Tests added
• Documentation added (where applicable)
• Changelog item added to changelog/

[bouweandela]

• Once we have the sample data in place, regression test output can be generated with a command like pytest --slow --force-regen -k ozone-lat-time as described here: https://climate-ref.readthedocs.io/en/latest/development/#tests-and-code-quality. Regression tests themselves can then be run by leaving out the --force-regen parameter. No additional code for testing is needed. If you already have the sample data generated locally from Add cmip6 and obs4mips data for ESMValTool ozone diagnostic  ref-sample-data#58, you could already run the tests locally to make sure things work. I usually replace this line

  climate-ref/conftest.py

  Line 103 in 01eabb5

  return test_data_dir / "sample-data"

  so it returns the path to my local copy of the sample data when I want to do this. I also discussed making this easier in the future with @lewisjared, resulting in Reworking sample data #472, but I'm not sure when that will be implemented.
• Could you please run pre-commit install and pre-commit run -a to fix the formatting issue?
• Could you please add a changelog? Similar to 2dd39d8 but replace the number in the filename by the number of this pull request.