improve tracking logic

src/app/components/test-suite/assessments/text-legibility-assessment/text-legibility-assessment.component.ts

@@ -48,8 +48,8 @@ export class TextLegibilityAssessmentComponent implements AfterViewInit, OnDestr
   }
 
   ngAfterViewInit() {
-    this.metricsService.startDeviceOrientationTracking();
-    this.metricsService.startArTracking(this.modelViewerRef.nativeElement);
+    const mv = this.modelViewerRef.nativeElement;
+    this.metricsService.startTracking(mv);
   }
 
   public logInteraction(event: Event) {