refactor(SidebarNavLink): add item.href for explicit external links

Author: xidedix

projects/coreui/angular/src/lib/sidebar/app-sidebar-nav/app-sidebar-nav-link.component.html

@@ -9,7 +9,7 @@
   </a>
   <a *ngSwitchCase="'external'"
      [ngClass]="getLinkClass()"
-     [href]="item.url"
+     [href]="href"
      [appHtmlAttr]="item.attributes"
   >
     <i *ngIf="helper.hasIcon(item)" [ngClass]="item | appSidebarNavIcon"></i>

projects/coreui/angular/src/lib/sidebar/app-sidebar-nav/app-sidebar-nav-link.component.ts

@@ -22,7 +22,7 @@ export class AppSidebarNavLinkComponent implements OnInit {
 
   ngOnInit() {
     this.linkType = this.getLinkType();
-    this.href = this.isDisabled() ? '' : this.item.url;
+    this.href = this.isDisabled() ? '' : (this.item.href || this.item.url);
   }
 
   public getLinkClass() {
@@ -49,7 +49,7 @@ export class AppSidebarNavLinkComponent implements OnInit {
   }
 
   public isExternalLink() {
-    return this.item.url.substring(0, 4) === 'http';
+    return !!this.item.href || this.item.url.substring(0, 4) === 'http';
   }
 
   public hideMobile() {