Fix #30072 : Add Generic version of EntityTypeConfiguration Attribute

[OsamaAbuSitta]

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        Summary of the changes
        - I add generic version of `EntityTypeConfigurationAttribute<TConfiguration, TEntity>` in the EFCore poject
        - I add Test method in `EntityTypeConfigurationAttribute_should_apply_configuration_to_EntityType_Generic`

        Fixes #30072

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[OsamaAbuSitta]

@dotnet-policy-service agree

[ajcvickers]

Thanks for the contribution!