[llvm] [workflows] Add top-level permissions for libcxx-build-and-test.yaml (PR #73689)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-github-workflow

Author: Tom Stellard (tstellar)

<details>
<summary>Changes</summary>

This is the standard convention for our workflow files.

---
Full diff: https://github.com/llvm/llvm-project/pull/73689.diff


1 Files Affected:

- (modified) .github/workflows/libcxx-build-and-test.yaml (+3) 


``````````diff
diff --git a/.github/workflows/libcxx-build-and-test.yaml b/.github/workflows/libcxx-build-and-test.yaml
index dccfe54d4646767..e929c02d11c1d93 100644
--- a/.github/workflows/libcxx-build-and-test.yaml
+++ b/.github/workflows/libcxx-build-and-test.yaml
@@ -23,6 +23,9 @@ on:
       - 'cmake/**'
       - '.github/workflows/libcxx-build-and-test.yaml'
 
+permissions:
+  contents: read # Default everything to read-only
+
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number }}
   cancel-in-progress: true

``````````

</details>


https://github.com/llvm/llvm-project/pull/73689