Support ajax form functionality with floating UI

Problem/Motivation

Currently, the module does not support enabling ajax form functionality with the invisible captcha / floating UI option enabled.

Proposed resolution

When the submit button is pressed, the floating UI should appear so altcha can verify the user.
After verification, the next submit button press should actually submit the form.

Remaining tasks

• Make it work.
• Update the description in the altcha settings form: Enables altcha floating UI. This feature is currently not supported on AJAX forms.