Duplicate plugin/preset detected. In Ember engine's inside inRepoEngine /test_client/lib/test-admin/index.js

In test_client/package.json
```
"ember-cli-babel": "^8.2.0",
"ember-cli-code-coverage": "^3.0.1",
```

In test_client/ember-cli-build.js
```
let app = new EmberAddon(defaults, {
// Add options here
autoImport: {
insertScriptsAt: 'auto-import-scripts',
webpack: {
externals: {
'jquery': 'jQuery'
}
}
},
babel: {
plugins: [...require('ember-cli-code-coverage').buildBabelPlugin()]
},
```

In test_client/index.js
```
included(app) {
this._super.included.apply(this, arguments);
if (this.project.pkg.name === this.name) {
this.options.babel.plugins.push(...require('ember-cli-code-coverage').buildBabelPlugin());
}
}
```
The below one is added In /test_client/lib/test-admin/index.js [In repo Engine]
```
included: function(/* app */) {
this._super.included.apply(this, arguments);
if (this.project.pkg.name === this.name) {
this.options.babel.plugins.push(...require('ember-cli-code-coverage').buildBabelPlugin()); //NO I18N
}
},
```
But it show error "Duplicate plugin/preset detected. If you'd like to use two separate instances of a plugin, they need separate names, e.g. plugins: [ ['some-plugin', {}], ['some-plugin', {}, 'some unique name'], ] " error