chore: add a step to load adk-bot SSH Private Key for the release analysis workflow

PiperOrigin-RevId: 807479079

Author: xuanyang15

.github/workflows/analyze-releases-for-adk-docs-updates.yml

@@ -23,6 +23,11 @@ jobs:
         with:
           python-version: '3.11'
 
+      - name: Load adk-bot SSH Private Key
+        uses: webfactory/ssh-agent@v0.9.0
+        with:
+          ssh-private-key: ${{ secrets.ADK_BOT_SSH_PRIVATE_KEY }}
+
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip