[3.9] bpo-42361: Update macOS installer build to use Tcl/Tk 8.6.11 (GH-24081) by miss-islington · Pull Request #24086 · python/cpython

As of 2021-01-03, Tcl/Tk 8.6.11rc2 is expected to be the final release.
(cherry picked from commit a38e04b)

Co-authored-by: Ned Deily nad@python.org

https://bugs.python.org/issue42361

Automerge-Triggered-By: GH:ned-deily