* Make CertFile and KeyFile relative to CustomPath
The current code will absolute CertFile and KeyFile against the current working directory. This is quite unexpected for users. This code makes relative paths absolute against the CustomPath.
Fix#4196
* Improve error reporting when reading certificates
* Apply suggestions from code review
Co-Authored-By: guillep2k <18600385+guillep2k@users.noreply.github.com>
Co-authored-by: guillep2k <18600385+guillep2k@users.noreply.github.com>