dropping embroider-optimized

Because the shenanigans with the custom mergeTrees here:

```js
appTree = new MergeTree(['tests/dummy/app', 'tests/colocation/app']);
```

Breaks staticComponents.

And also, I don't think this addon is particularly important to test under embroider-optimized anyway.

Author: ef4

.github/workflows/ci.yml

@@ -84,7 +84,6 @@ jobs:
          - ember-classic
          - ember-default-with-jquery
          - embroider-safe
-         - embroider-optimized
          - with-ember-cli-htmlbars-inline-precompile
 
     steps:

config/ember-try.js

@@ -1,7 +1,7 @@
 'use strict';
 
 const getChannelURL = require('ember-source-channel-url');
-const { embroiderSafe, embroiderOptimized } = require('@embroider/test-setup');
+const { embroiderSafe } = require('@embroider/test-setup');
 
 module.exports = async function () {
   return {
@@ -84,7 +84,6 @@ module.exports = async function () {
         },
       },
       embroiderSafe(),
-      embroiderOptimized(),
       {
         name: 'with-ember-cli-htmlbars-inline-precompile',
         npm: {