Add new directive for UI tests

frontend/src/app/data-cy.directive.ts

@@ -0,0 +1,13 @@
+import { Directive, ElementRef, Renderer2 } from '@angular/core';
+import { environment } from '../environments/environment';
+
+@Directive({
+  selector: '[data-cy]'
+})
+export class DataCyDirective {
+  constructor(private el: ElementRef, private renderer: Renderer2) {
+    if (environment.production) {
+      renderer.removeAttribute(el.nativeElement, 'data-cy');
+    }
+  }
+}