[Form] Fixed usage of "name" variable in form_start block
bug #12291 [Form] Fixed usage of "name" variable in form_start block (webmozart)

This PR was merged into the 2.5 branch.

Discussion
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[Form] Fixed usage of "name" variable in form_start block

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #10192
| License       | MIT
| Doc PR        | -

Commits
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5839832 [Form] Fixed usage of "name" variable in form_start block