chore(package): update @angular-devkit/schematics to version 8.1.2

Closes #49

Author: greenkeeper[bot]

demo/package.json

@@ -50,7 +50,7 @@
   "devDependencies": {
     "@angular-devkit/build-angular": "^0.10.7",
     "@angular-devkit/core": "^7.3.5",
-    "@angular-devkit/schematics": "^7.3.5",
+    "@angular-devkit/schematics": "^8.1.2",
     "@angular/cli": "^7.3.5",
     "@angular/compiler-cli": "^7.2.8",
     "@angular/language-service": "^7.2.8",