[llvm] [workflows] Use a custom token for creating backport PRs (PR #79501)

[Nikita Popov via llvm-commits]

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@@ -61,7 +61,7 @@ jobs:
           printf "%s" "$COMMENT_BODY" |
           ./llvm/utils/git/github-automation.py \
           --repo "$GITHUB_REPOSITORY" \
-          --token ${{ github.token }} \
+          --token "${{ secrets.RELEASE_WORKFLOW_PR_CREATE }}" \
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nikic wrote:

Just to double check, does this token also have permission to create issue comments? It will be used for that as well.

https://github.com/llvm/llvm-project/pull/79501