Turn link to change password form in admin user change form into a button

[Fabian Braun]

Currently, to change a user's password the admin user must got to the change user form, find the password field and click a link in its help text.

For better user guidance and accessibility, I suggest turning this link into a button:

As David Smith pointed out, links in help texts are not read by screen readers:

"Do not include links within hint text. While screen readers will read out the link text when describing the field, they will not tell users that the text is a link." (​https://design-system.service.gov.uk/components/text-input/#hint-text).

I'll be happy to provide a patch.

[Fabian Braun]

Current link to change password form