maintainer-feedback requested: [Bug 264611] multimedia/gstreamer1-editing-services: update to 1.16.3 and use meson to fix Python issues

Bugzilla Automation <bugzilla@FreeBSD.org> has asked freebsd-multimedia
(Nobody) <multimedia@FreeBSD.org> for maintainer-feedback:
Bug 264611: multimedia/gstreamer1-editing-services: update to 1.16.3 and use
meson to fix Python issues
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=264611



--- Description ---
gstreamer1-editing-services does not support Python 3.10 (reported by VVD) and
also misdetects it if multiple versions installed, would give preference to 2.7
if installed.

vishwin and diizzy pointed out that gstreamer supports meson build, so let's go
for it. vishwin has done some testing; versus his suggestion, my port drops the
Perl5 dep and keeps the bash completion, and also adds gst-validator support.