Adds renovate-bot support (#24)

#### 📖 Summary

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#### 📑 Test Plan

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- [x] Tested via CI pipeline
- [ ] Custom test
- [ ] No test plan

##### Details / Justification

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#### 📚 Additional Notes

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Co-authored-by: OCram85 <marco.blessing@googlemail.com>
Reviewed-on: #24

.woodpecker/.renovate.yml

@@ -0,0 +1,21 @@
+pipeline:
+  DockerBaseImage:
+    image: renovate/renovate:34.22-slim
+    commands:
+      - "renovate"
+    secrets:
+      - RENOVATE_TOKEN
+    environment:
+      #LOG_LEVEL: debug
+      RENOVATE_PLATFORM: "gitea"
+      RENOVATE_ENDPOINT: "https://gitea.ocram85.com"
+      RENOVATE_REPOSITORIES: "${CI_REPO}"
+      RENOVATE_LABELS: "renovate"
+      #RENOVATE_DRY_RUN: "full"
+      RENOVATE_TOKEN: "${RENOVATE_TOKEN}"
+    when:
+      event:
+        - push
+      branch:
+        - master
+        - updDeps