TestUriSchemes unittest failing randomly

[drodarie]

This seems to happen only in parallel for the GHA. Maybe linked to #187

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  ERROR: test_nm_scheme (test_util.TestUriSchemes.test_nm_scheme)
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  Traceback (most recent call last):
    File "/home/runner/work/bsb/bsb/packages/bsb-core/tests/test_util.py", line 79, in test_nm_scheme
      meta = file.get_meta()
             ^^^^^^^^^^^^^^^
    File "/home/runner/work/bsb/bsb/packages/bsb-core/bsb/storage/_files.py", line 98, in get_meta
      not check_store or ((stored := self.get_stored_file()) is None)
                                     ^^^^^^^^^^^^^^^^^^^^^^
    File "/home/runner/work/bsb/bsb/packages/bsb-core/bsb/storage/_files.py", line 133, in get_stored_file
      return self.file_store.find_meta("source", self._given_source)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/home/runner/work/bsb/bsb/packages/bsb-core/bsb/storage/interfaces.py", line 358, in find_meta
      return self.find_file(lambda _, meta: meta.get(key, None) == value)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/home/runner/work/bsb/bsb/packages/bsb-core/bsb/storage/interfaces.py", line 352, in find_file
      return next(self.find_files(predicate), None)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/home/runner/work/bsb/bsb/packages/bsb-core/bsb/storage/interfaces.py", line 348, in find_files
      StoredFile(self, id_) for id_, m in self.all().items() if predicate(id_, m)
                                          ^^^^^^^^^^
    File "/home/runner/work/bsb/bsb/packages/bsb-core/bsb/storage/fs/file_store.py", line 37, in all
      id: self.get_meta(id) for id in map(_path_to_id, os.listdir(self.file_path()))
          ^^^^^^^^^^^^^^^^^
    File "/home/runner/work/bsb/bsb/packages/bsb-core/bsb/storage/fs/file_store.py", line 147, in get_meta
      return self._get_meta(id)["meta"]
             ^^^^^^^^^^^^^^^^^^
    File "/home/runner/work/bsb/bsb/packages/bsb-core/bsb/storage/fs/file_store.py", line 141, in _get_meta
      return json.load(f)
             ^^^^^^^^^^^^
    File "/usr/lib/python3.12/json/__init__.py", line 293, in load
      return loads(fp.read(),
             ^^^^^^^^^^^^^^^^
    File "/usr/lib/python3.12/json/__init__.py", line 346, in loads
      return _default_decoder.decode(s)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/usr/lib/python3.12/json/decoder.py", line 337, in decode
      obj, end = self.raw_decode(s, idx=_w(s, 0).end())
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/usr/lib/python3.12/json/decoder.py", line 355, in raw_decode
      raise JSONDecodeError("Expecting value", s, err.value) from None
  json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)
  
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