Uppercasing the geography code results in Geography not found exceptions

[adieyal]

wazimap-ng/wazimap_ng/datasets/dataloader.py

Line 16 in 21e1e63

geo_code = str(geo_code).upper()

Instead of uppercasing the code, we should match with the exact string from the dataset

[milafrerichs]

please also write a test with wrong code and correct geo codes