[Form] Accept interfaces to be passed to "data_class"
[Form] Added test case for 4759e062ed004749dbdc2ba31aef0f8ac2601895
feature #10569 [Form] Accept interfaces to be passed to "data_class" (webmozart)

This PR was merged into the 2.5-dev branch.

Discussion
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[Form] Accept interfaces to be passed to "data_class"

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8669
| License       | MIT
| Doc PR        | -

Commits
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b44e07b [Form] Added test case for 4759e062ed004749dbdc2ba31aef0f8ac2601895
7bc7a8a [Form] Accept interfaces to be passed to "data_class"