git errors (non-blocking) when running make

[sxa]

Looking at the most recently builds from v24 it looks like there are git errors showing up when the main make is run in the unofficial-builds. Slightly different errors per platform but consistently broken. We should probably look at clearing this up. I haven't looked at any other platforms.

Platform	Error
alpine/musl	/bin/sh: git: not found
loong64	fatal: not a git repository (or any of the parent directories): .git
riscv64	fatal: not a git repository (or any of the parent directories): .git

[richardlau]

FWIW These are coming from the release-only target, which is a dependency of the binary target.