chore(package): update @angular/cli to version 8.3.18

Closes #42

Author: greenkeeper[bot]

package.json

@@ -40,7 +40,7 @@
     "zone.js": "~0.9.1",
     "firebase": "^6.3.0",
     "@angular-devkit/build-angular": "~0.801.1",
-    "@angular/cli": "~8.1.1",
+    "@angular/cli": "~8.3.18",
     "@angular/compiler-cli": "~8.1.1",
     "@angular/language-service": "~8.1.1",
     "tslint": "~5.15.0",