spec(tooltip): revert from inital to none as its the computed style

Author: simeonoff

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

@@ -529,7 +529,7 @@ describe('IgxTooltip', () => {
             verifyTooltipVisibility(tooltipNativeElement, tooltipTarget, true);
 
             const maxWidth = getComputedStyle(tooltipNativeElement).maxWidth;
-            expect(maxWidth).toBe('initial');
+            expect(maxWidth).toBe('none');
         }));
     });