[llvm] [workflows] Split pr-code-format into two parts to make it more secure (PR #78216)

[Aiden Grossman via llvm-commits]

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@@ -44,6 +44,7 @@ class FormatArgs:
     token: str = None
     verbose: bool = True
     issue_number: int = 0
+    write_comment_to_file: bool = False
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boomanaiden154 wrote:

There will be some dead code in this file now that the logic for actually posting the comment lives in a different workflow. I'm fine leaving refactoring that to a follow-up patch though.

https://github.com/llvm/llvm-project/pull/78216