BUG: fix Index.reindex to preserve name when target is list/ndarray
This PR fixes #6552 and also includes:

CLN: drop copy_if_needed kwarg of Index.reindex, it's True everywhere
TST: enable back empty-list loc/ix tests that failed before
DOC: Bump Index.reindex docstring

looks good, ping on green
 green. do you want me to add that GHXXXX tag on the test now?
 yep

just rebase and add that tag
after u push just ping and can merge
 rebased & added
 thanks!
