Compatibility with SQLA2.1

[Dev-iL]

This PR is intended to ensure compatibility with SQLA2.1.

The plan is as follows:

• Force installing 2.1 (prerelease if necessary) in the context of the Latest SQLAlchemy test: core and Latest SQLAlchemy test: providers tasks.
• Fix any incompatibilities / raise bug reports in the SQLA repo.
• Revert forcing the latest version and keep the compatibility fixes

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