chore(deps): update dependency @angular-devkit/build-angular to v0.12.4

Author: renovate-bot

package-lock.json

@@ -34,7 +34,7 @@
     "zone.js": "0.8.29"
   },
   "devDependencies": {
-    "@angular-devkit/build-angular": "0.12.3",
+    "@angular-devkit/build-angular": "0.12.4",
     "@angular/cli": "7.2.3",
     "@angular/compiler-cli": "7.2.3",
     "@angular/language-service": "7.2.3",