TST: skip test_groupby_rolling_index_changed on 32bit
this is against 1.1.x directly. see https://github.com/pandas-dev/pandas/issues/35831#issuecomment-688862692
test_groupby_rolling_empty_frame just added in #36213 is not failing on 32 bit, yet all other tests nearby have the skip.

https://dev.azure.com/pandas-dev/pandas-wheels/_build/results?buildId=41860&view=results restarted https://github.com/MacPython/pandas-wheels/pull/97 to check.