Update JamesIves/github-pages-deploy-action action to v4.7.3

Author: elastic-renovate-prod[bot]

.github/workflows/gh-pages.yml

@@ -31,7 +31,7 @@ jobs:
         run: npm run build && npm run export && touch ./out/.nojekyll
 
       - name: Deploy 🚀
-        uses: JamesIves/github-pages-deploy-action@v4.4.1
+        uses: JamesIves/github-pages-deploy-action@6c2d9db40f9296374acc17b90404b6e8864128c8 # v4.7.3
         with:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           BRANCH: gh-pages # The branch the action should deploy to.