[llvm] [CI] fix possibly undefined variable in code-format job (PR #165454)

[Baranov Victor via llvm-commits]

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vbvictor wrote:

Possibly using variable 'comments' before assignmentPylint [E0606:possibly-used-before-assignment](https://pylint.readthedocs.io/en/latest/user_guide/messages/error/possibly-used-before-assignment.html)

https://github.com/llvm/llvm-project/pull/165454