chore: 🤖 upgrade to ember source 3.28

addons/api/mirage/config.js

@@ -1,4 +1,3 @@
-import Ember from 'ember';
 import config from '../config/environment';
 import { authHandler, deauthHandler } from './route-handlers/auth';
 import { pickRandomStatusString } from './factories/session';
@@ -6,6 +5,8 @@ import { Response } from 'miragejs';
 import initializeMockIPC from './scenarios/ipc';
 import makeBooleanFilter from './helpers/bexpr-filter';
 
+const isTesting = config.environment === 'test';
+
 export default function () {
   initializeMockIPC(this);
 
@@ -417,7 +418,7 @@ export default function () {
       // update alternate sessions to auth user.
       // But only if not in testing mode.
       // In tests, we need deterministic statuses.
-      if (!Ember.testing) {
+      if (!isTesting) {
         sessions.all().models.forEach((session) => {
           session.update({
             status: pickRandomStatusString(),
@@ -446,7 +447,7 @@ export default function () {
   );
   this.get('/sessions/:id', function ({ sessions }, { params: { id } }) {
     const session = sessions.find(id);
-    if (!Ember.testing) {
+    if (!isTesting) {
       session.update({
         status: pickRandomStatusString(),
       });

addons/api/mirage/scenarios/ipc.js

@@ -1,7 +1,8 @@
-import Ember from 'ember';
 import config from 'ember-get-config';
 import { datatype } from 'faker';
 
+const isTesting = config.environment === 'test';
+
 export default function initializeMockIPC(server) {
   /**
    * We strive to make this application runnable in a regular web browser, since
@@ -149,7 +150,7 @@ export default function initializeMockIPC(server) {
    *
    * Initializes mock IPC only in a non-Electron non-testing context.
    */
-  if (!config.isElectron && !Ember.testing) {
+  if (!config.isElectron && !isTesting) {
     const mockIPC = new MockIPC();
     window.addEventListener('message', async function (event) {
       if (event.origin !== window.location.origin) return;

addons/api/package.json

@@ -43,7 +43,7 @@
     "broccoli-asset-rev": "^3.0.0",
     "doctoc": "^2.0.1",
     "ember-auto-import": "^1.12.0",
-    "ember-cli": "~3.28.0",
+    "ember-cli": "~3.28.3",
     "ember-cli-dependency-checker": "^3.2.0",
     "ember-cli-inject-live-reload": "^2.1.0",
     "ember-cli-sri": "^2.1.1",
@@ -57,7 +57,7 @@
     "ember-page-title": "^6.2.2",
     "ember-qunit": "^5.1.4",
     "ember-resolver": "^8.0.3",
-    "ember-source": "~3.24.0",
+    "ember-source": "~3.28.4",
     "ember-source-channel-url": "^3.0.0",
     "ember-template-lint": "^3.7.0",
     "ember-try": "^1.4.0",