CI: re-enable downstream test for geopandas (#29993)

Author: jorisvandenbossche

pandas/tests/test_downstream.py

@@ -102,10 +102,7 @@ def test_pandas_datareader():
 
 
 # importing from pandas, Cython import warning
-@pytest.mark.filterwarnings("ignore:The 'warn':DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:pandas.util:DeprecationWarning")
 @pytest.mark.filterwarnings("ignore:can't resolve:ImportWarning")
-@pytest.mark.skip(reason="gh-25778: geopandas stack issue")
 def test_geopandas():
 
     geopandas = import_module("geopandas")  # noqa