Appveyor config fixes

.appveyor.yml

@@ -25,10 +25,14 @@ init:
 # Set clone depth (do not fetch complete history)
 clone_depth: 5
 
-# Skipping commits affecting only specific files
+# Skip commits affecting only specific files
 skip_commits:
   files:
-    - 'documentation/*'
+    # Removed - 'documentation/*'
+    # Unfortunately Appveyor only looks at the HEAD (latest) commit, so if
+    # the last commit pushed to a PR only updates the Release Notes the whole
+    # PR build gets skipped. GitHub Actions looks at the complete list
+    # of files changed since its last build, which is much more useful.
     - 'startup/*'
     - '.github/*'
     - '.tools/*'