move to devdependencies

Signed-off-by: Fredrik Adelöw <freben@gmail.com>

plugins/code-coverage/package.json

@@ -33,7 +33,6 @@
     "@material-ui/icons": "^4.9.1",
     "@material-ui/styles": "^4.11.0",
     "@material-ui/lab": "4.0.0-alpha.57",
-    "@types/highlightjs": "^10.1.0",
     "highlight.js": "^10.6.0",
     "react": "^16.13.1",
     "react-dom": "^16.13.1",
@@ -48,6 +47,7 @@
     "@testing-library/jest-dom": "^5.10.1",
     "@testing-library/react": "^10.4.1",
     "@testing-library/user-event": "^12.0.7",
+    "@types/highlightjs": "^10.1.0",
     "@types/jest": "^26.0.7",
     "@types/node": "^12.0.0",
     "@types/recharts": "^1.8.15",