Bump matrix-org/netlify-pr-preview from 2 to 3 (#16719)

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/docs-pr-netlify.yaml

@@ -22,7 +22,7 @@ jobs:
           path: book
 
       - name: 📤 Deploy to Netlify
-        uses: matrix-org/netlify-pr-preview@v2
+        uses: matrix-org/netlify-pr-preview@v3
         with:
           path: book
           owner: ${{ github.event.workflow_run.head_repository.owner.login }}