Trying to install from source fails (see partial traceback below) because it can't find Python 3.10 module "asciidoc".

Package "asciidoc" is install on my system, as a Python 3.8 module (the default version on FreeBSD).

Build would probably succeed if I removed Python 3.9 + 3.10 from my system. I think the Makefile doesn't determine the default version of Python correctly.

---

FAILED: djxl.1 /usr/ports/graphics/libjxl/work/.build/djxl.1 
cd /usr/ports/graphics/libjxl/work/.build && /usr/local/bin/python3.10 /usr/local/bin/a2x --format manpage --destination-dir="/usr/ports/graphics/libjxl/work/.build" /usr/ports/graphics/libjxl/work/libjxl-0.6.1/doc/man/djxl.txt
Traceback (most recent call last):
  File "/usr/local/bin/a2x", line 33, in <module>
    sys.exit(load_entry_point('asciidoc==10.1.3', 'console_scripts', 'a2x')())
  File "/usr/local/bin/a2x", line 22, in importlib_load_entry_point
    for entry_point in distribution(dist_name).entry_points
  File "/usr/local/lib/python3.10/importlib/metadata/__init__.py", line 928, in distribution
    return Distribution.from_name(distribution_name)
  File "/usr/local/lib/python3.10/importlib/metadata/__init__.py", line 518, in from_name
    raise PackageNotFoundError(name)