Update dependency styletron-engine-atomic to v1.2.0

Author: renovate-bot

packages/iotex-react-block-producers/package.json

@@ -103,7 +103,7 @@
     "react-dom": "16.8.6",
     "react-test-renderer": "16.8.6",
     "source-map-loader": "0.2.4",
-    "styletron-engine-atomic": "1.1.0",
+    "styletron-engine-atomic": "1.2.0",
     "ts-node": "8.2.0",
     "tslint": "5.16.0",
     "tslint-config-prettier": "1.18.0",