Feature: #97392 - Use password policy for new admin users created in ext:install

See forge#97392


The password for a new administrative backend user created using EXT:install now considers the configurable password policy introduced by #97388.


The global password policy is now taken into account when a new administrative backend user is created using EXT:install. Password policy requirements are shown below the password field and a message is shown, if the new password does not meet the password policy requirements.