[llvm] [libc++] Move the check-generated-files job to Github Actions (PR #68920)

[Tobias Hieta via llvm-commits]

================
@@ -0,0 +1,25 @@
+name: "Check libc++ generated files"
+on:
+  pull_request:
+    paths:
+      - 'libcxx/**'
+
+jobs:
+  check_generated_files:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Fetch LLVM sources
+        uses: actions/checkout at v4
+        with:
----------------
tru wrote:

You can remove this unless you need to use `git-clang-format`, it's only there so we can diff.

https://github.com/llvm/llvm-project/pull/68920