www/py-flask-migrate: Fix build after 59c51372a83e96bcd8314a60bf91a0d82a9f0f94

• Change RUN_DEPENDS from py-flask-sqlalchemy30 (py-sqlalchemy14) to py-flask-sqlalchemy (py-sqlalchemy20)
• Bump PORTREVISION for dependency change

Reference: https://pkg-status.freebsd.org/beefy22/data/142amd64-default/4ff0a7ba4d1f/logs/py311-flask-migrate-4.0.7.log

		https://pkg-status.freebsd.org/beefy21/data/142i386-default/4ff0a7ba4d1f/logs/py311-flask-migrate-4.0.7.log