fix: packages/backend/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-PROTOBUFJS-5756498

Author: snyk-io[bot]

packages/backend/package.json

@@ -34,7 +34,7 @@
     "@backstage/integration": "workspace:^",
     "@backstage/plugin-adr-backend": "workspace:^",
     "@backstage/plugin-app-backend": "workspace:^",
-    "@backstage/plugin-auth-backend": "workspace:^",
+    "@backstage/plugin-auth-backend": "0.1.1",
     "@backstage/plugin-auth-node": "workspace:^",
     "@backstage/plugin-azure-devops-backend": "workspace:^",
     "@backstage/plugin-azure-sites-backend": "workspace:^",
@@ -51,7 +51,7 @@
     "@backstage/plugin-graphql-backend": "workspace:^",
     "@backstage/plugin-jenkins-backend": "workspace:^",
     "@backstage/plugin-kafka-backend": "workspace:^",
-    "@backstage/plugin-kubernetes-backend": "workspace:^",
+    "@backstage/plugin-kubernetes-backend": "0.1.1",
     "@backstage/plugin-lighthouse-backend": "workspace:^",
     "@backstage/plugin-linguist-backend": "workspace:^",
     "@backstage/plugin-nomad-backend": "workspace:^",