install explicit go version

Author: bahkauv70

.github/workflows/renovate.yaml

@@ -5,13 +5,20 @@ on:
     - cron: "0 0 * * *"
   workflow_dispatch:
 
+env:
+  GOVERSION: 1.21.13
+
 jobs:
   renovate:
     name: Renovate
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v4
+      - name: Install Go ${{env.GOVERSION}}
+        uses: actions/setup-go@v5
+        with:
+          go-version: ${{env.GOVERSION}}
       - name: Self-hosted Renovate
         uses: renovatebot/github-action@v41.0.0
         with: