Use Renovate in self-hosted mode

Signed-off-by: Bence Hornák <bence.hornak@gmail.com>

Author: bencehornak

.github/renovate-self-hosted.json

@@ -0,0 +1,7 @@
+{
+  "allowedCommands": ["^./gradlew kotlinUpgradeYarnLock$"],
+  "onboarding": true,
+  "platform": "github",
+  "repositories": ["open-feature/kotlin-sdk-contrib"],
+  "semanticCommits": "enabled"
+}

.github/workflows/renovate.yaml

@@ -0,0 +1,21 @@
+name: Renovate
+on:
+  schedule:
+    - cron: '0 8 * * *' # At 8:00 AM daily (UTC)
+
+  # Allow manual triggering
+  workflow_dispatch:
+
+jobs:
+  renovate:
+    runs-on: ubuntu-latest
+    steps:
+
+      - name: Checkout
+        uses: actions/checkout@v5
+
+      - name: Self-hosted Renovate
+        uses: renovatebot/github-action@v43.0.11
+        with:
+          configurationFile: .github/renovate-self-hosted.json
+          token: ${{ secrets.RENOVATE_BOT }}