Add indication for required next to Confirm Password

[kouratoras]

In new user and edit user screens, if you choose to manually add a password and this password is not strong enough, a "Confirm Password" checkbox appears. "Add New User" or "Update Profile" (depending on which of the 2 screens you currently are) button is disabled, until you check this "Confirm Password" checkbox.

But, as there is no indication that you have to check this checkbox in order the submit button to be enabled, I suggest to add a "(required)" indication next to it, so the user knows what is missing to enable the button.

I attach a screen on how I suggest the screen to look like.
I also attach a patch that adds this indication in both add and edit user screens.

[kouratoras]

Screenshot indicating the issue

[lukecavanagh]

Add New User Screen

## Description

This PR adds a required indication next to the 'Confirm Password' checkbox on the new user and edit user screens. This helps users understand that they need to check this checkbox to enable the 'Add New User' or 'Update Profile' button when the manually added password is not strong enough. The update improves clarity and user experience by clearly indicating the required action.

## Screenshots

• Add User

• Edit User

## Trac ticket: https://core.trac.wordpress.org/ticket/37284

[nirajgirixd]

It's a small ​PR. Could someone please review and either approve or provide feedback?

cc: @kouratoras, @lukecavanagh