Breaking nightly tests due to pandas-dev/pandas#65429

[cmp0xff]

After pandas-dev/pandas#65429, we see the following additional errors in nightly tests
81

FAILED tests/arrays/test_timedeltas.py::test_timedelta_array_freq - AttributeError: 'TimedeltaArray' object has no attribute 'freq'
FAILED tests/arrays/test_timedeltas.py::test_timedelta_array_freqstr - AttributeError: 'TimedeltaArray' object has no attribute 'freqstr'