gh-95841: IDLE - Revise Windows local doc url (GH-95845)

GH-91242 replaced the Windows chm help file with a copy
of the html docs.  This PR replaces the IDLE code that
fetches the Windows local help url passed to os.startfile.
Co-authored-by: Steve Dower
(cherry picked from commit bdb2cf8e913c041f26e8976abe58414819b3e8ff)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>