feat: Support MySQL FOR SHARE locking syntax.

feat: Support MySQL FOR SHARE locking syntax.

Added support for MySQL 8.0.1 + ``FOR SHARE`` to be emitted for the
:meth:`.Select.with_for_uddate` method, which offers compatibility with
``NOWAIT`` and ``SKIP LOCKED``.  The new syntax is used only for MySQL when
version 8.0.1 or higher is detected. Pull request courtesy JetDrag.

Fixes: #10134
Closes: #12964
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/12964
Pull-request-sha: 03d5e37cfda5da9dab8ae00aa682521f8ab9190b

Change-Id: Iafb7a24363284edcfeead94a348f50a470a88403
(cherry picked from commit 59afd08a5206c69ce47c138c6e4f18b2c40e1ef6)