Removed unused variables in FunctionCommentSniff.php

[gy741]

Description

Hello,

I have remove unused variable.

Because it is not used.

What do you think of it?

Thanks.

Fixed Issues (if relevant)

N/A

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/verification tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)
• Changes to Framework doesn't have backward incompatible changes for tests or have related Pull Request with fixes to tests

[coveralls]

Coverage remained the same at 57.482% when pulling d6e0b77 on gy741:remove_dead_code_v2 into 4c8b297 on magento:develop.

[coveralls]

Coverage increased (+0.008%) to 57.054% when pulling 1f780e7 on gy741:remove_dead_code_v2 into bf2143d on magento:develop.

[KevinBKozan]

@gy741 Thank you for your contribution! We will update this PR with progress information as we process it.

[okolesnyk]

@gy741 Please take a look at comment I left.