Test enhancement for assertion call and usages

[peter279k]

Changed log

• Using the * to let all branch name can be triggered on GitHub Actions.
• Remove $settings variable because it's assigned, but not used.
• Using the assertNull to assert expected is null.
• Using the assertFalse to assert expected is false.
• Using the assertTrue to assert expected is true.
• According to the PHPUnit fixtures reference, the setUp method is protected function setUp(): void and the tearDown method is protected function teaDown(): void.

[sj-i]

👍

[sj-i]

thanks!