removed "providedIn" from @Injectable DataSyncService (for compatibility with older Angular versions)

Author: rjohnson465

projects/gojs-angular/package.json

@@ -1,6 +1,6 @@
 {
   "name": "gojs-angular",
-  "version": "1.0.15",
+  "version": "1.0.16",
   "peerDependencies": {
     "@angular/common": ">=11.0.0",
     "@angular/core": ">=11.0.0"

projects/gojs-angular/src/lib/data-sync.service.ts

@@ -1,9 +1,7 @@
 import { Injectable } from '@angular/core';
 import * as go from 'gojs';
 
-@Injectable({
-  providedIn: 'root'
-})
+@Injectable()
 export class DataSyncService {
 
   constructor() { }

projects/gojs-angular/src/lib/gojs-angular.module.ts

@@ -1,4 +1,5 @@
 import { NgModule } from '@angular/core';
+import { DataSyncService } from './data-sync.service';
 import { DiagramComponent } from './diagram.component';
 import { OverviewComponent } from './overview.component';
 import { PaletteComponent } from './palette.component';
@@ -11,6 +12,9 @@ import { PaletteComponent } from './palette.component';
   ],
   imports: [
   ],
+  providers: [
+    DataSyncService
+  ],
   exports: [
     DiagramComponent,
     OverviewComponent,