DBAL-1246: [GH-867] Fix fk schemadiff renamed column

[doctrinebot]

Jira issue originally created by user @doctrinebot:

This issue is created automatically through a Github pull request on behalf of zeroedin-bill:

Url: #867

Message:

In situations where SQL is generated with SchemaDiff::toSaveSql, foreign keys for columns that have been renamed or removed were not being dropped if the referenced table was orphaned.

[github-actions]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.