[php8-compat][NFC] Ensure that the 2nd parameter of hash_equals is a …

[seamuslee001]

…string in authx

Overview

This fixes the following error when found running unit tests on php8

ERROR\n\n The website encountered an unexpected error. Please try again later. \n\nERROR MESSAGE\n\n _TypeError_: hash_equals(): Argument #2 ($user_string) must be of type\nstring, null given in _hash_equals()_ (line _161_ of\n_/home/jenkins/bknix-edge/build/build-1/web/sites/all/modules/civicrm/ext/authx/Civi/Authx/Authenticator.php_)

Before

Error found in unit tests

After

no error

Technical Details

A simple cast here should do the trick

ping @eileenmcnaughton @demeritcowboy @totten

[civibot]

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