BUG: fix reindexing with a tz-aware index and method='nearest'
- [x] closes #26683
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

First pandas PR, happy to make changes as needed.  Is a whatsnew entry needed?  And if so, I assume it should go in v1.0.1.rst? 
Thanks @MarcoGorelli for the guidance!  Is there anything else I can improve?  Docs build fail seems unrelated, transient network error?  https://github.com/pandas-dev/pandas/pull/31511/checks?check_run_id=419939179#step:6:37 @kanderso-nrel likely a network issue, you could add a whatsnew note in `1.1` and try it again @jreback all green after #31594 thanks!