This is most likely only happening because you are changing the password with root and by default root is allowed to do whatever root wants.

If you su - test375 and then try to set your own password it would most likely fail. However you want to check /etc/pam.d/common-password and ensure it has this line:

password requisite pam_pwquality.so retry=3 

Which it most likely does because otherwise you wouldn't get that warning. If you really want to ensure root can't set unsecure passwords you can modify that line to:

password requisite pam_pwquality.so retry=3 enforce_for_root

This will enforce the password policy even when sudo is used.

This is most likely only happening because you are changing the password with sudo and by default root is allowed to do whatever root wants.

If you su - test375 and then try to set your own password as a regular user, it would most likely fail. However you want to check /etc/pam.d/common-password and ensure it has this line:

password requisite pam_pwquality.so retry=3 

Which it most likely does because otherwise you wouldn't get that warning. If you really want to ensure root can't set unsecure passwords you can modify that line to:

password requisite pam_pwquality.so retry=3 enforce_for_root

This will enforce the password policy even when sudo is used.