remove uneeded fixture

conftest.py

@@ -48,19 +48,6 @@ def netcdf4_file(tmpdir):
     return filepath
 
 
-@pytest.fixture
-def chunked_netcdf4_file(tmpdir):
-    # Set up example xarray dataset
-    ds = xr.tutorial.open_dataset("air_temperature")
-
-    # Save it to disk as netCDF (in temporary directory)
-    filepath = f"{tmpdir}/air.nc"
-    ds.chunk(time=1460).to_netcdf(filepath, format="NETCDF4")
-    ds.close()
-
-    return filepath
-
-
 @pytest.fixture
 def netcdf4_file_with_data_in_multiple_groups(tmpdir):
     filepath = str(tmpdir / "test.nc")