[Form] corrected interface bind() method defined against in deprecation notice
merged branch shieldo/correct_bind_interface (PR #8248)

This PR was merged into the 2.2 branch.

Discussion
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[Form] corrected interface bind() method defined against in deprecation ...

...notice

The 'bind' method is defined against `FormInterface` not `FormConfigInterface`. This corrects the deprecation notice in the `Form` implementation.

Commits
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de289d2 [Form] corrected interface bind() method defined against in deprecation notice