Some ports uses git while make configure to load deps

Hi!


I see this many times with different ports, for example: graphics/evince.
Probably this is new meson behaviour.

...
Run-time dependency libhandy-1 found: YES 1.6.2
Library m found: YES
Found CMake: /usr/local/bin/cmake (3.24.3)
Run-time dependency gi-docgen found: NO (tried pkgconfig and cmake)
Looking for a fallback subproject for the dependency gi-docgen
Cloning into 'gi-docgen'...
remote: Enumerating objects: 151, done.
remote: Counting objects: 100% (151/151), done.
remote: Compressing objects: 100% (131/131), done.
remote: Total 151 (delta 22), reused 105 (delta 17), pack-reused 0
Receiving objects: 100% (151/151), 2.48 MiB | 638.00 KiB/s, done.
Resolving deltas: 100% (22/22), done.

Executing subproject gi-docgen 

gi-docgen| Project name: gi-docgen
gi-docgen| Project version: 2022.3
gi-docgen| Program nonexistingprogram (jinja2, markdown, markupsafe, pygments, toml, typogrify) found: NO

gi-docgen| subprojects/gi-docgen/meson.build:10:0: Exception: python3 not found

...


Does it violates some ports requirements to not load anything that not covered by "make makesum"?