Fix changing the user name when creating a new account. As it always takes the first part of the email

Problem/Motivation

When creating a new account from /admin/people/create and set the user name, it always takes the first part of the email, until save and edit the user then change the name to take a new name.

Steps to reproduce

- Install Drupal
- Install and enable the Email Registration module.
- Go to /admin/people/create
- Fill in the fields and change the user name.
- Submit the form.
- After submitting the form, the user name is not as it was filled before, it will be the first part of the email.

Proposed resolution

I suggest in email_registration_form_user_form_alter to give the user name default value rather than value, by replace
$form['account']['name']['#value'] = 'email_registration_' . user_password(); with
$form['account']['name']['#default_value'] = 'email_registration_' . user_password();