Split to kafka backend plugin

plugins/kafka/package.json

@@ -25,7 +25,6 @@
     "@material-ui/core": "^4.11.0",
     "@material-ui/icons": "^4.11.2",
     "@material-ui/lab": "4.0.0-alpha.45",
-    "kafkajs": "^1.15.0",
     "lodash": "^4.17.20",
     "react": "^16.13.1",
     "react-dom": "^16.13.1",
@@ -35,6 +34,7 @@
     "@backstage/cli": "^0.4.2",
     "@backstage/dev-utils": "^0.1.6",
     "@backstage/test-utils": "^0.1.5",
+    "@backstage/plugin-kafka-backend": "^0.1.1",
     "@testing-library/jest-dom": "^5.10.1",
     "@testing-library/react": "^10.4.1",
     "@testing-library/user-event": "^12.0.7",