Add missing dist check

.github/workflows/check-dist.yml

@@ -10,10 +10,12 @@
 name: Check Transpiled JavaScript
 
 on:
+  pull_request:
+    branches:
+      - main
   push:
     branches:
       - main
-  pull_request:
 
 permissions:
   contents: read
@@ -48,6 +50,11 @@ jobs:
       - name: Compare Directories
         id: diff
         run: |
+          if [ ! -d dist/ ]; then
+            echo "Expected dist/ directory does not exist.  See status below:"
+            ls -la ./
+            exit 1
+          fi
           if [ "$(git diff --ignore-space-at-eol --text dist/ | wc -l)" -gt "0" ]; then
             echo "Detected uncommitted changes after build. See status below:"
             git diff --ignore-space-at-eol --text dist/