[ruby/reline] Ignore non-absolute XDG_CONFIG_HOME
https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
All paths set in these environment variables must be absolute. If an implementation encounters a relative path in any of these variables it should consider the path invalid and ignore it.
https://github.com/ruby/reline/commit/45af6eea77
[ruby/reline] Ignore non-absolute XDG_CONFIG_HOME
https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
https://github.com/ruby/reline/commit/45af6eea77