Fixed FutureWarning regarding the use of GeoDataFrame and GeoSeries for data...

Fixed FutureWarning regarding the use of GeoDataFrame and GeoSeries for data without geopandas geometry (switched to plain pandas classes).

Signed-off-by: Daniel Scheffler <danschef@gfz-potsdam.de>
5 jobs for master in 23 minutes and 8 seconds (queued for 1 second)
Status Job ID Name Coverage
  Test
passed test_gms_preprocessing #49869

00:09:56

63.0%
passed test_gms_preprocessing_install #49870

00:12:36

passed test_styles #49871

00:00:20

 
  Deploy
passed pages #49872

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passed pages:deploy

00:00:01