Add get_one to Session, AsyncSession, scoped, etc

Add get_one to Session, AsyncSession, scoped, etc

Added method :meth:`_orm.Session.get_one` that behaves like
meth:`_orm.Session.get` but raises an exception instead of returning
None`` if no instance was found with the provided primary key.
Pull request courtesy of Carlos Sousa.

Fixed the :paramref:`_asyncio.AsyncSession.get.execution_options` parameter
which was not being propagated to the underlying :class:`_orm.Session` and
was instead being ignored.

Fixes #10292
Closes: #10376
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/10376
Pull-request-sha: 70e4505e93905ee3cebc52f828a95c6bf987c9be

Change-Id: I78eb9816c26446757b6c6c171df2e400777a3d36