minor #14901 [Form] add test to avoid regression of #14891 (xabbuh)
minor #14901 [Form] add test to avoid regression of #14891 (xabbuh)

This PR was merged into the 2.6 branch.

Discussion
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[Form] add test to avoid regression of #14891

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #14891
| License       | MIT
| Doc PR        |

Commits
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12a19c8 [Form] add test to avoid regression of #14891

symfony/Form