[3.7] gh-95778: Mention sys.set_int_max_str_digits() in error message (GH-96874)...

[3.7] gh-95778: Mention sys.set_int_max_str_digits() in error message (GH-96874) (GH-96877) (GH-97836)

[3.9] gh-95778: Mention sys.set_int_max_str_digits() in error message (GH-96874) (GH-96877)

When ValueError is raised if an integer is larger than the limit,
mention sys.set_int_max_str_digits() in the error message.

(cherry picked from commit e841ffc915e82e5ea6e3b473205417d63494808d)

Co-authored-by: Ned Deily <nad@python.org>
(cherry picked from commit 41188134bd2120f0cedd681ed88743c11c7f3742)

Co-authored-by: Victor Stinner <vstinner@python.org>