[llvm] [Github][CI] Add note about AI tools in good-first-issue text (PR #173109)

[Baranov Victor via llvm-commits]

================
@@ -28,7 +28,7 @@
 
 1. Check that no other contributor is working on this issue. If someone is assigned to the issue or claimed to be working on it, ping the person. After one week without a response, the assignee may be changed.
 1. Leave a comment indicating that you are working on the issue, or just create a [pull request](https://github.com/llvm/llvm-project/pulls) after following the steps below. [Mention](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue) this issue in the description of the pull request.
-1. Fix the issue locally.
+1. Fix the issue locally. Note that using AI tools to fix is forbidden by [LLVM Developer Policy](https://llvm.org/docs/DeveloperPolicy.html#ai-generated-contributions).
----------------
vbvictor wrote:

If you have a better wording, suggestions are welcome.

There are some suggestions from _AI_, maybe you like it more:

- "Fix the issue locally, but do not use AI tools to generate code fixes, as this is prohibited by the [LLVM Developer Policy](https://llvm.org/docs/DeveloperPolicy.html#ai-generated-contributions)."
- "Fix the issue locally without using AI tools. The [LLVM Developer Policy](https://llvm.org/docs/DeveloperPolicy.html#ai-generated-contributions) prohibits AI-generated code contributions."

https://github.com/llvm/llvm-project/pull/173109