chore: set explicit go toolchain version to avoid SDK updates

Author: bahkauv70

.github/workflows/renovate.yaml

@@ -14,6 +14,8 @@ jobs:
         uses: actions/checkout@v4
       - name: Self-hosted Renovate
         uses: renovatebot/github-action@v41.0.0
+        env: 
+          GOTOOLCHAIN: go1.21.13
         with:
           configurationFile: .github/renovate.json
           token: ${{ secrets.RENOVATE_TOKEN }}