Issue 49646 - Improve TLS cert processing in lib389 CLI
Description: Add a new option to setup.inf file - self_sign_cert_valid_months
which accepts int value. dscreate should renew Self-signed CA if
it is expired or it will expire less than in 2 months.
Also, we need to import it to other existing instances.
Remove the NSS DB in the test topology during a teardown.
Fix small issues in nss_tls_test.
Add format_cmd_list function to utils.py. It returns a nicely formatted
quoted representation of the command list we put into subprocess call.
Add more logging to nss_tls.py. Change the default validity period to 24 months.
https://pagure.io/389-ds-base/issue/49646
Reviewed by: mreynolds, tbordaz, mhonek (Thanks!)