Log Message:
pkgtools/pkglint: update to 23.14.0

Changes since 23.13.0:

Fix wrong warnings about MASTER_SITE_BACKUP being not known.

Reduce the amount of log data when tracing variables that repeatedly
use `+=` to append to a variable.

Support the `.-include` directive, the `.ifmake` directive and the
built-in `<` variable, to be able to check standalone makefiles
outside pkgsrc.

Complain about merge conflicts in makefiles, which were silently ignored
before.

Complain about package patterns whose bounds contradict each other,
such as `pkgbase>=2<1`, as these never match and are probably typos.

Do not warn about pkgsrc-wip packages that are missing a COMMIT_MSG file,
as long as they have a TODO file, as it is fine to have work-in-progress
packages in pkgsrc-wip.