include peer deps into dev

Author: xkam

package.json

@@ -40,6 +40,7 @@
     "@angular/common": "^8",
     "@angular/compiler": "^8",
     "@angular/compiler-cli": "^8",
+    "@angular/core": "^8",
     "@angular/platform-browser": "^8",
     "@angular/platform-browser-dynamic": "^8",
     "@babel/core": "^7",