fix(package): update @angular/pwa to version 0.901.0

Closes #33

Author: greenkeeper[bot]

package.json

@@ -38,7 +38,7 @@
     "@angular/platform-browser": "^8.2.0",
     "@angular/platform-browser-dynamic": "^8.2.0",
     "@angular/platform-server": "^8.2.0",
-    "@angular/pwa": "^0.803.0",
+    "@angular/pwa": "^0.901.0",
     "@angular/router": "^8.2.0",
     "@angular/service-worker": "^8.2.0",
     "@nguniversal/express-engine": "8.1.1",