chore(deps): update webfactory/ssh-agent action to v0.9.1

Author: anaconda-renovate[bot]

.github/workflows/release.yml

@@ -123,7 +123,7 @@ jobs:
       run: cd docs && poetry run sphinx-build -b html . _build
 
     - name: Setup SSH key
-      uses: webfactory/ssh-agent@d4b9b8ff72958532804b70bbe600ad43b36d5f2e # v0.8.0
+      uses: webfactory/ssh-agent@a6f90b1f127823b31d4d4a8d96047790581349bd # v0.9.1
       with:
         ssh-private-key: ${{ secrets.DOCS_DEPLOY_SSH_KEY }}