Duplicated GADM_IDs appeared in gadm_shapes

[CUIJING03]

Checklist

• I am using the current main branch or the latest release. Please indicate.

• I am running on an up-to-date pypsa-earth environment. Update via conda env update -f envs/environment.yaml.

Describe the Bug

When I updated to version 0.4.0, I found that the rule build_bus_regions does not work. The associated logs indicated the error as ValueError: All arrays must be of the same length. after debugging build_bus_regions.py I found that there were multiple duplicate GADM_IDs appearing (as shown here). One additional point I would like to add, I used alternative_clustering.

The first figure shows the specifics of a pair of duplicate GADM_IDs, and the second figure embodies all the duplicate GADM_IDs

[CUIJING03]

My build_bus_regions log is as follows:

INFO:pypsa.io:Imported network base.nc has buses, lines, links, transformers
ERROR:_helpers:An error happened in module 'D:\\Anaconda3\\envs\\pypsa-earth\\lib\\site-packages\\pandas\\core\\internals\\construction.py', function '_extract_index': All arrays must be of the same length
Traceback (most recent call last):
  File "D:\pypsa-earth-project\pypsa-earth\.snakemake\scripts\tmpmtwwtd5g.build_bus_regions.py", line 205, in <module>
    temp_region = gpd.GeoDataFrame(
  File "D:\Anaconda3\envs\pypsa-earth\lib\site-packages\geopandas\geodataframe.py", line 139, in __init__
    super().__init__(data, *args, **kwargs)
  File "D:\Anaconda3\envs\pypsa-earth\lib\site-packages\pandas\core\frame.py", line 778, in __init__
    mgr = dict_to_mgr(data, index, columns, dtype=dtype, copy=copy, typ=manager)
  File "D:\Anaconda3\envs\pypsa-earth\lib\site-packages\pandas\core\internals\construction.py", line 503, in dict_to_mgr
    return arrays_to_mgr(arrays, columns, index, dtype=dtype, typ=typ, consolidate=copy)
  File "D:\Anaconda3\envs\pypsa-earth\lib\site-packages\pandas\core\internals\construction.py", line 114, in arrays_to_mgr
    index = _extract_index(arrays)
  File "D:\Anaconda3\envs\pypsa-earth\lib\site-packages\pandas\core\internals\construction.py", line 677, in _extract_index
    raise ValueError("All arrays must be of the same length")
ValueError: All arrays must be of the same length

[davide-f]

Great spot @CUIJING03 !
You may check if this code works:

pypsa-earth/scripts/build_shapes.py

Lines 1292 to 1297 in 1bd7f84

	# renaming 3 letter to 2 letter ISO code before saving GADM file
	# In the case of a contested territory in the form 'Z00.00_0', save 'AA.00_0'
	# Include bugfix for the case of 'XXX00_0' where the "." is missing, such as for Ghana
	df_gadm["GADM_ID"] = df_gadm["country"] + df_gadm["GADM_ID"].str[3:].apply(
	lambda x: x if x.find(".") == 0 else "." + x
	)

Moreover if you open a PR about it, it would be great if you could move this fix into the function filder_gadm

pypsa-earth/scripts/build_shapes.py

Line 126 in 1bd7f84

def filter_gadm(