[llvm] [Workflows] Enable commit access requests via GitHub issues (PR #100458)

[Vlad Serebrennikov via llvm-commits]

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@@ -27,3 +27,6 @@
 
 'bolt':
   - '/\bbolt(?!\-)\b/i'
+
+'infrastructure:commit-access-request':
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Endilll wrote:

Can we use a shorter label? Maybe `infra:commit-access`.

https://github.com/llvm/llvm-project/pull/100458