[3.12] gh-69001: Convert links to more usable buttons (GH-129591) (#130339)

gh-69001: Convert links to more usable buttons (GH-129591)

In Lib/idlelib/help_about.py, there are 2 links that are not underlined or colored, hence hard to tell that clicking works.  All buttons might get converted to colored and underlined links in the future.
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(cherry picked from commit ed831b95a231ef949da13a261b40ee1ea0e126d7)

Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>