Add Support for ALTCHA on all PKP systems

[Godoy0722]

Description
All PKP systems currently support Google Recaptcha. I'm creating this Issue to solve issue #10456, which was created to add support for ALTCHA integration, a Google Recaptcha alternative.

These improvements were made for the Default theme, on userLogin, userRegister, and userLostPassword pages.

Finally, for this support to work, the config.inc.php must be updated with the new variables as I also created PRs as follows:

• OPS/775
• OJS/4446
• OMP/1703

To Reproduce
Steps to reproduce the behavior:

1. Starting on the root directory of any system, Run composer --working-dir=lib/pkp install
2. Update the config.inc.php file with the new variables as shown on the other PRs, and set altcha and altcha_on_login as on
3. Enter on login page and click on submit button

[Godoy0722]

Closing as this issue is a duplicated one for the #10283.