group storage with duplicate labels

[lindnemi]

Closes # (if applicable).

Changes proposed in this Pull Request

fixes an error that occurs when h2 storage is built at the same bus but at different snapshots

Traceback (most recent call last):
  File "/home/micha/git/pypsa-ariadne/.snakemake/scripts/tmp53wos82s.plot_network.py", line 1105, in <module>
    plot_h2_map(n, regions)
  File "/home/micha/git/pypsa-ariadne/.snakemake/scripts/tmp53wos82s.plot_network.py", line 278, in plot_h2_map
    regions["H2"] = h2_storage.rename(
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/geopandas/geodataframe.py", line 1543, in __setitem__
    super().__setitem__(key, value)
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/frame.py", line 4091, in __setitem__
    self._set_item(key, value)
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/frame.py", line 4300, in _set_item
    value, refs = self._sanitize_column(value)
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/frame.py", line 5036, in _sanitize_column
    return _reindex_for_setitem(value, self.index)
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/frame.py", line 12309, in _reindex_for_setitem
    raise err
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/frame.py", line 12304, in _reindex_for_setitem
    reindexed_value = value.reindex(index)._values
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/series.py", line 4981, in reindex
    return super().reindex(
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/generic.py", line 5521, in reindex
    return self._reindex_axes(
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/generic.py", line 5544, in _reindex_axes
    new_index, indexer = ax.reindex(
  File "/home/micha/micromamba/envs/pypsa-ariadne/lib/python3.10/site-packages/pandas/core/indexes/base.py", line 4434, in reindex
    raise ValueError("cannot reindex on an axis with duplicate labels")
ValueError: cannot reindex on an axis with duplicate labels

Checklist

• I tested my contribution locally and it seems to work fine.
• Code and workflow changes are sufficiently documented.
• Changed dependencies are added to envs/environment.yaml.
• Changes in configuration options are added in all of config.default.yaml.
• Changes in configuration options are also documented in doc/configtables/*.csv.
• A release note doc/release_notes.rst is added.

[FabianHofmann]

could you remove these changes?

[lindnemi]

good spot, that was an accident!

[fneum]

Looks good and also works for overnight scenarios.