Fixes #20604 - Treat ToString as casting to string in the database

[Danevandy99]

Fixes #20604

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[Danevandy99]

The build Helix task seems to be stuck, but I'm not sure how to fix that.

[Danevandy99]

@roji #33706 adds functionality that makes ToString on enums more useful when the enum is mapped to an int in the database.

[roji]

Yeah, I see - it's just that we probably need to discuss a broader strategy here when it comes to ToString, value conversion, etc. beyond just the enum case.

[Danevandy99]

Merging changes with https://github.com/dotnet/efcore/pull/33706