CLN: remove is_period_arraylike, is_datetime_arraylike
There are better alternatives
needs a rebase. are these public? if so need to deprecate (unfortunately) and provide a shim. > are these public?

no @WillAyd any idea why mypy would be complaining here (and i think on many other PRs) but not locally? Can you merge master? @simonjayhawkins had a recent fix for mypy @jbrockmendel can you merge master rebased+green