[3.12] gh-109234: Hint to contextlib.closing in sqlite3 context manager docs (GH-109322) (#110294)

(cherry picked from commit 4227bfa8b273207a2b882f7d69c8ac49c3d2b57d)

Co-authored-by: Lincoln <71312724+Lincoln-developer@users.noreply.github.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Erlend E. Aasland <erlend@python.org>