Feature: Adds test for login, logout, forgot-password and reset-password

[jakob-info]

Fixes #540, fixes #542, fixes #543.
Implements feature tests for api routes:

• /auth/login
• /auth/logout
• /auth/register
• /auth/forgot-password
• /reset.password/{reset_token} (get and post)

I chose not to validate if the jwt token is correct. In my opinion, PHPUnit tests are for that.
I chose to duplicate some code and split the assertions in two tests because i didn't want the test function name to get too long because it tests different functionality.

• I have read the contributing guidelines.
• My code is of good quality and follows the coding standards of the project.
• I have tested my changes, and they work as expected.

Thank you for your contribution! 🎉

[daveearley]

Nice! Thank you very much for these changes