fix(deps): update dependency @backstage-community/plugin-todo-backend to ^0.20.0

Author: renovate[bot]

backstage/packages/backend/package.json

@@ -17,7 +17,7 @@
   },
   "dependencies": {
     "@axis-backstage/plugin-readme-backend": "^0.12.0",
-    "@backstage-community/plugin-todo-backend": "^0.12.0",
+    "@backstage-community/plugin-todo-backend": "^0.20.0",
     "@backstage/backend-common": "^0.25.0",
     "@backstage/backend-tasks": "^0.6.1",
     "@backstage/catalog-client": "^1.9.1",