Update dependency eslint-plugin-react to v7.20.0

Author: renovate-bot

package.json

@@ -105,7 +105,7 @@
     "eslint-plugin-jest": "23.11.0",
     "eslint-plugin-jsx-a11y": "6.2.3",
     "eslint-plugin-prettier": "3.1.3",
-    "eslint-plugin-react": "7.19.0",
+    "eslint-plugin-react": "7.20.0",
     "eslint-watch": "6.0.1",
     "file-loader": "6.0.0",
     "koa-connect": "2.0.1",