TST/REF: arithmetic tests for BooleanArray + consolidate with integer masked tests
Follow-up on https://github.com/pandas-dev/pandas/pull/34454

- Move a bunch of tests from `integer/test_arithmetic.py` to `masked/test_arithmetic.py` so those can be shared with boolean (and once merged I can add float as well in the FloatingArray PR)
- Added some more arithmetic tests to `boolean/test_arithmetic.py` to follow the same pattern as we have in `integer/test_arithmetic.py`. 
- The commong integer/boolean tests uncovered a bug in the BooleanArray implementation when dealing with a `pd.NA` scalar as other operand.
small comment; LGTM Updated for all comments thanks @jorisvandenbossche 