chore: add chai dependency to e2e app

Author: Elena Hristova

e2e/renderer/package.json

@@ -31,6 +31,7 @@
     "babel-traverse": "6.26.0",
     "babel-types": "6.26.0",
     "babylon": "6.18.0",
+    "chai": "^4.2.0",
     "lazy": "1.0.11",
     "mocha": "~5.2.0",
     "mochawesome": "~3.1.2",