List changed files when failing due to dist directory change

Hopefully this will help track down spurious failures.

.github/workflows/ci-check-no-dist-update.yml

@@ -2,6 +2,7 @@ name: CI-check-no-dist-update
 
 # Prohibit any change to 'dist/**' on a non-release branch
 on:
+  workflow_dispatch:
   push:
     branches-ignore:
       - 'main'
@@ -15,8 +16,27 @@ permissions:
 jobs:
   fail-on-dist-update:
     runs-on: ubuntu-latest
-
     steps:
+    - name: Checkout sources
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+
+    - name: Get changed files
+      id: changed-files
+      uses: tj-actions/changed-files@v44
+      with:
+        files: |
+          dist/**
+
+    - name: Print changes to dist directory
+      env:
+        ALL_CHANGED_FILES: ${{ steps.changed-files.outputs.all_changed_files }}
+      run: |
+        for file in ${ALL_CHANGED_FILES}; do
+          echo "$file was changed"
+        done
+
     - run: |
         echo "The 'dist' directory is auotmatically updated by the release process."
         echo "It should not be updated manually in a non-release branch or a pull request."