The caching idea is somewhat flawed, as there's a lot of things that
cane effect the outcome, and they're difficult to boil down into a
single unique key.
Update the build-emacs-for-macos to v0.5.0, which includes a new
emacs-builder CLI tool written in Go, which handles signing, dmg
packaging, notarizing and stapling of Emacs builds. The main build
process is still handled by the old Ruby script for now however.
emacs-builder also includes plan and release commands, negating the need
for the our custom github-release CLI tool.
BREAKING CHANGE: Release assets are now signed *.dmg files instead
of *.tbz archives.
This will allow creating test builds using any branch of
build-emacs-for-macos or emacs-builds repos, so experimental changes can
be verified without affecting the nightly builds.
