feat(dashboard): improve form UX

[lucacacciarru]

Description

At this moment, there is no check if the user changes or adds valid input inside the collection/global forms, which means that we are firing useless onSubmit every time the user clicks the button even if the data are unchanged.

Solutions

The best solution at the moment would be to make the submit button disabled when the user doesn't add a different value than the previous one.

[plushdohn]

related #17