[Issue] Fix typo in PHPDoc block

[m2-assistant]

This issue is automatically created based on existing pull request: #38940: Fix typo in PHPDoc block

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Description (*)

This PR remove a unknown referenced variable in PHPDoc for $helper variable declaration.

Manual testing scenarios (*)

This fix has no testing scenario, because is a code typo.

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• README.md files for modified modules are updated and included in the pull request if any README.md predefined sections require an update
• All automated tests passed successfully (all builds are green)