[Form] ObjectChoiceList now compares choices by their value, if a value path is given
feature #10572 [Form] ObjectChoiceList now compares choices by their value, if a value path is given (webmozart)

This PR was merged into the 2.5-dev branch.

Discussion
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[Form] ObjectChoiceList now compares choices by their value, if a value path is given

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8825
| License       | MIT
| Doc PR        | -

Commits
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ce0efb1 [Form] ObjectChoiceList now compares choices by their value, if a value path is given