Fix element attribute for MS icon in the example
Fix element attribute for MS icon in the example

Currently, we have an error with the example in the build:
``èrror
The 'element' property of the icon for browserconfig.xml must be one of square70x70logo, square150x150logo, wide310x150logo, square310x310logo
```
san650/ember-web-app,san650/ember-web-app