Run notes:push steps only if there are changes

Taskfile.yml

@@ -46,9 +46,11 @@ tasks:
   notes:push:
     desc: Commit and push changes to notes submodule
     dir: '{{.NOTES_DIR}}'
+    preconditions:
+      - sh: git add NOTES.md && ! git diff --cached --quiet
+        msg: "No changes to commit"
     cmds:
-      - git add NOTES.md
-      - git diff --cached --quiet || git commit -m "Update notes - $(date '+%Y-%m-%d %H:%M')"
+      - git commit -m "Update notes - $(date '+%Y-%m-%d %H:%M')"
       - git push
     silent: false