[BUG] Missing support for empty-name traits

version: 0.14.8

I marked this as a bug, but it could be understood as a missing feature as well. Basically, grapesjs-blocks-bootstrap4 has some traits with an empty name, given that those traits set the (bootstrap) classes of the elements. The problem is that, as I understand it, grapesjs did not expect traits to have empty names, and expected them to always map 1-to-1 with the element attributes.

This bug/missing feature might be detected by following these steps:

• Use the grapesjs-blocks-bootstrap4 plugin.
• Use the index.html example there - Make sure to enable the storageManager
• Add any bootstrap block, eg: Alert
• In the Component Settings page, change one of its bootstrap props which change its class, eg: set context to primary
• Reload the page so it re-reads from the storage
• Click the View code button
• This results in invalid html being shown:

<div ="alert-primary" class="alert alert-primary">This is an alert—check it out!</div>

Screenshot