Per review, simplify disabling of default action

Turns out you can just call `event.preventDefault()` on the action and
there is no need actually use hotkeys to do that.

app/components/tag_list_input_component/tag_list_input_controller.js

@@ -3,15 +3,10 @@ import { Controller } from "stimulus";
 export default class extends Controller {
   static targets = ["tagList", "newTag", "template", "list"];
 
-  connect() {
-    // form hotkeys are enabled for "input" scope, we disable the form submit via enter
-    // on the tag input, so we can use the enter key to create new product tag
-    hotkeys("enter", { scope: "input", element: this.newTagTarget }, function () {
-      event.preventDefault();
-    });
-  }
+  addTag(event) {
+    // prevent hotkey form submitting the form (default action for "enter" key)
+    event.preventDefault();
 
-  addTag() {
     // Check if tag already exist
     const newTagName = this.newTagTarget.value.trim();
     if (newTagName.length == 0) {

spec/javascripts/stimulus/tag_list_input_controller_test.js

@@ -9,14 +9,6 @@ describe("TagListInputController", () => {
   beforeAll(() => {
     const application = Application.start();
     application.register("tag-list-input-component--tag-list-input", tag_list_input_controller);
-
-    // Mock hotkeys.js
-    const mockedHotkeys = jest.fn();
-    global.hotkeys = mockedHotkeys;
-  });
-
-  afterAll(() => {
-    delete global.hotkeys;
   });
 
   beforeEach(() => {