feat: add a component selector to the dropdown menu

Closes #8

Author: mattlewis92

src/text-input-autocomplete-menu.component.ts

@@ -2,6 +2,7 @@ import { Component, ElementRef, HostListener, ViewChild } from '@angular/core';
 import { Subject } from 'rxjs';
 
 @Component({
+  selector: 'mwl-text-input-autocomplete-menu',
   template: `
     <ul 
       *ngIf="choices?.length > 0"

test/text-input-autocomplete.directive.spec.ts

@@ -374,4 +374,14 @@ describe('text-input-autocomplete directive', () => {
       expect(() => arrowDown(CustomMenuComponent)).not.to.throw();
     })
   );
+
+  it(
+    'should add a component selector to the menu for global styling',
+    fakeAsync(() => {
+      typeInTextarea('test @');
+      expect(getMenu().nativeElement.tagName.toLowerCase()).to.equal(
+        'mwl-text-input-autocomplete-menu'
+      );
+    })
+  );
 });