When this was originally added, some OS package managers were slow and
behind the required meson version needed for mpv to build. Both opensuse
tumbleweed and freebsd now appear to carry meson 0.60.3 in their repos
so we no longer need to do the two-step process of installing pip3 and
then installing meson via pip. Instead, just use the OS package manager
version.
Update the github workflows to also do meson builds for every OS.
Additionally, make every workflow execute the built mpv executable
(except for windows and FreeBSD's waf executable) to make sure that it
runs. As an aside, FreeBSD unfortunately is a bit less elegant since it
is in a VM.
This CI builder bases on openSUSE Tumbleweed, and recently had
its glibc updated. This led to new syscalls such as 'clone3' not
being allowed through the security layer.
Can be reverted after Github Actions updates their security policy.
actions/virtual-environments#3812