git sha of ports tree used to build packages from

hi,

is there any way to know what commit was used from the ports tree, as the
base for the package builders? If not, can this be exposed somehow, maybe
in something like meta.conf ?

$ curl http://pkg.freebsd.org/FreeBSD:14:amd64/latest/meta.conf

version = 2;
packing_format = "txz";
manifests = "packagesite.yaml";
filesite = "filesite.yaml";
manifests_archive = "packagesite";
filesite_archive = "filesite";

I could use this commit to ensure my local poudriere ports branch isn't
ahead of what is pre-built on the official mirrors, and only rebase
up to what's there.

This would be a huge help in avoiding needless local poudriere rebuilds
when my ports tree is ahead of whatever the builders have done. Nothing
like watching cmake* openjdk* llvm* rust* etc starting up when all you
really needed was some trivial leaf package.

A+
Dave