Improve usability of sshd_lineinfile template

#### Description of problem:
The newly introduced parameter `is_default_value` to the [`sshd_lineinfile`](https://github.com/ComplianceAsCode/content/tree/master/shared/templates/sshd_lineinfile) template does not represent the behavior of the template when this parameter is used.

The parameter decides the configuration file name for products like RHEL9 and similar ones that make use of the `sshd_config.d` drop-in files.

The parameter was first introduced in:

https://github.com/ComplianceAsCode/content/pull/8179

The idea here is to make things more explicit and concise.

@yuumasato FYI