Document use of skip-precommit-approval label for non-review pull requests (#81053)

Derived from this discussion:
https://discourse.llvm.org/t/prs-without-approvals-muddy-the-waters/76656

Author: dwblaikie

llvm/docs/CodeReview.rst

@@ -103,6 +103,12 @@ ready to be committed. Specifically, once a patch is sent out for review, it
 needs an explicit approval before it is committed. Do not assume silent
 approval, or solicit objections to a patch with a deadline.
 
+.. note::
+   If you are using a Pull Request for purposes other than review
+   (eg: precommit CI results, convenient web-based reverts, etc)
+   `skip-precommit-approval<https://github.com/llvm/llvm-project/labels?q=skip-precommit-approval>`
+   label to the PR.
+
 Acknowledge All Reviewer Feedback
 ---------------------------------
 

llvm/docs/GitHub.rst

@@ -30,6 +30,12 @@ describes the typical workflow of creating a Pull Request and getting it reviewe
 and accepted. This is meant as an overview of the GitHub workflow, for complete
 documentation refer to `GitHub's documentation <https://docs.github.com/pull-requests>`_.
 
+.. note::
+   If you are using a Pull Request for purposes other than review
+   (eg: precommit CI results, convenient web-based reverts, etc)
+   `skip-precommit-approval<https://github.com/llvm/llvm-project/labels?q=skip-precommit-approval>`
+   label to the PR.
+
 GitHub Tools
 ------------
 You can interact with GitHub in several ways: via git command line tools,