REF: merge.py check for known arraylikes
#48454 was going to do this as a deprecation, but before that got merged another PR accidentally made most weird-arraylikes raise (making it difficult to write a test for the deprecation).  We agreed to wait a while to see if anyone complained about that, then to change over the checks explicitly.  Among other things this will make the existing AnyArrayLike annotations in this file accurate.
Thanks @jbrockmendel 