fix(package): update electron to version 4.0.0

Author: greenkeeper[bot]

package.json

@@ -57,7 +57,7 @@
     "@angular/platform-browser-dynamic": "^7.1.1",
     "@angular/router": "^7.1.1",
     "core-js": "^2.5.7",
-    "electron": "^3.0.10",
+    "electron": "^4.0.0",
     "ffi-napi": "^2.4.4",
     "ngx-electron": "^2.0.0",
     "rxjs": "^6.3.3",