PERF: isinstance ABCIndexClass and ABCExtensionArray
```
%timeit isinstance(pd.Series, pd.core.dtypes.generic.ABCIndexClass)
# 607 ns ± 12.4 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each) - PR
# 937 ns ± 37.5 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each) - Master


%timeit isinstance(pd.Series, pd.core.dtypes.generic.ABCExtensionArray)
# 634 ns ± 26.9 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each) - PR
# 759 ns ± 40.6 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each) - Master


%timeit isinstance(pd.Series, pd.core.dtypes.generic.ABCSeries)
# 638 ns ± 49.1 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each) - PR
# 644 ns ± 20.1 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each) - Master
```