ci: use 10up/action-wordpress-plugin-asset-update@stable

Author: carlalexander

.github/workflows/update-assets-readme.yml

@@ -10,7 +10,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - name: Update plugin assets and readme
-        uses: 10up/action-wordpress-plugin-asset-update@develop
+        uses: 10up/action-wordpress-plugin-asset-update@stable
         env:
           SVN_PASSWORD: ${{ secrets.SVN_PASSWORD }}
           SVN_USERNAME: ${{ secrets.SVN_USERNAME }}