Chore: Update ghcr.io/renovatebot/renovate Docker tag to v39

Author: grafanarenovatebot[bot]

.github/workflows/renovate-validate.yaml

@@ -13,5 +13,5 @@ jobs:
       - name: Validate renovate config
         run: |-
           # Renovate updates the line below. Please keep its formatting as it is.
-          export RENOVATE_IMAGE=ghcr.io/renovatebot/renovate:38.142.6@sha256:51f47d953e6c8ea46ba7acffcfc9151e7be9f27a7e0bc828388ff1e5207de1f3
+          export RENOVATE_IMAGE=ghcr.io/renovatebot/renovate:39.11.4@sha256:679645578b94bc6e7986bf4f0673ad98c56daa3fb45f100ea531d4e6c0da65da
           docker run -i --rm -v $(realpath .):/repo -w /repo --entrypoint renovate-config-validator "$RENOVATE_IMAGE" --strict

.github/workflows/renovate.yaml

@@ -37,7 +37,7 @@ jobs:
       - name: Self-hosted Renovate
         uses: renovatebot/github-action@dd4d265eb8646cd04fc5f86ff8bc8d496d75a251 # v40.2.8
         with:
-          renovate-version: 38.142.6@sha256:51f47d953e6c8ea46ba7acffcfc9151e7be9f27a7e0bc828388ff1e5207de1f3
+          renovate-version: 39.11.4@sha256:679645578b94bc6e7986bf4f0673ad98c56daa3fb45f100ea531d4e6c0da65da
           configurationFile: .github/renovate-app.json
           token: "${{ steps.app-token.outputs.token }}"
         env: