Add Ember 3.28 "normal" to CI

Author: mixonic

.github/workflows/ci.yml

@@ -147,6 +147,7 @@ jobs:
             ember-lts-3.16,
             ember-lts-3.20,
             ember-lts-3.24,
+            ember-lts-3.28,
             ember-release,
             ember-beta,
             ember-canary,

config/ember-try.js

@@ -53,6 +53,14 @@ module.exports = async function () {
           },
         },
       },
+      {
+        name: 'ember-lts-3.28',
+        npm: {
+          devDependencies: {
+            'ember-source': '~3.28.0',
+          },
+        },
+      },
       {
         name: 'ember-release',
         npm: {