[3.13] gh-135756: Fix nonexistent parameter in tkinter docs (GH-135770) (#135777)

gh-135756: Fix nonexistent parameter in tkinter docs (GH-135770)

Remove nonexistent color parameter from tkinter.commondialog.Dialog.show() method documentation.
(cherry picked from commit 4ddf505d9982dc8afead8f52f5754eea5ebde623)

Co-authored-by: Marcell Perger <102254594+MarcellPerger1@users.noreply.github.com>