chore(*): update IgxSelection to use overrideTemplateUsingTestingModule

Author: nrobakova

projects/igniteui-angular/src/lib/directives/text-selection/text-selection.directive.spec.ts

@@ -56,11 +56,7 @@ describe('IgxSelection', () => {
         const template = ` <input type="text" [igxTextSelection]="false" #select="igxTextSelection"
             (click)="select.trigger()" value="Some custom value!" />`;
 
-        TestBed.overrideComponent(TriggerTextSelectionOnClickComponent, {
-            set: {
-                template
-            }
-        });
+        TestBed.overrideTemplateUsingTestingModule(TriggerTextSelectionOnClickComponent, template);
 
         TestBed.compileComponents().then(() => {
             const fix = TestBed.createComponent(TriggerTextSelectionOnClickComponent);