Previously we'd discard everything after the second dash.

This also sets an additional variable if it detects that this is an alpha
or development build, which currently does nothing but might eventually
turn on the ability to use experimental features, if we make that
something available only in prereleases.

The actions/checkout workflow does some heroics to try to fetch exactly
the commit being built and nothing else, even if asked to fetch the
history leading up to that commit. That means we don't end up having
enough information to get an accurate answer from "git describe".

Since we're intentionally relying on the git history here, we'll fetch
all of the tags explicitly after initial checkout. Although that does add
some delay to this step, we're intentionally doing this version
calculation only once as a separate workflow job so that all of the other
jobs can still benefit from this action's quicker checkout behavior.

goenv was making things more complicated than needed since it's really
designed to help with interactive use in a shell more than automated use
like this.

Instead, we'll follow the same strategy that our build.yml was doing of
just reading the .go-version file directly and then using the official
actions/setup-go action to do the actual installation. The key advantage
here is that Go ends up installed in a way where just running "go" will
do the right thing, and we no longer need to fuss with shims and
version-based path prefixes.

Rather than duplicating the logic from build.yml, instead it's factored
out into a separate composite action which both build.yml and checks.yml
will now share, in case we want to change the Go version selection
methodology in the future.

Normally when we cross-compile we do so without CGo, because we don't have
suitable C headers available for systems other than the host.

However, building for macOS on macOS is special because there are
sufficient headers available on darwin_amd64 to build for both
darwin_amd64 _and_ darwin_arm64. Also, we _must_ use CGo on macOS because
the system resolver is only available via darwin's libc, and so building
without CGo produces executables that don't resolve hostnames correctly.

This is a conditional in bash to avoid having to duplicate the entire
step. Perhaps later we'll find a more general version of this which can
avoid the special case, but this is sufficient for the moment.

In our build workflow we'll treat Linux distribution packaging (currently
.deb and .rpm packages) as a separate job, instead of embedding it into
the "build" job, so that this step can happen concurrently with the other
derived actions like the docker image build, and the e2etest runs.

This workflow only generates artifacts and doesn't need to modify anything
about the repository.

We can use an extra matrix dimension to select which execution environment
we'll use for each GOOS/GOARCH pair, and thus avoid duplicating the
job definition for darwin just to set runs-on: macos-latest for it.

This is not really an intended use of a matrix dimension because it's
directly related to the existing "goos" one, rather than being an
independent third dimension, but it doesn't matter in practice because
we're using the "include" option to specify exact combinations, and thus
we're not relying on the built-in functionality to generate all possible
matrix combinations.

This should eventually grow to be a step that actually verifies the
validity of the docs source prior to publishing the artifact that a
downstream publishing pipeline can consume, but for the moment it's really
just a placeholder since we have no such validation step and no downstream
pipeline consuming this artifact.

The general idea here is that the artifacts from this workflow should be
sufficient for all downstream release steps to occur without any direct
access to the Terraform CLI repository, and so this is intended to
eventually meet that ideal but as of this commit the website docs
publishing step _does_ still depend on direct access to this repository.

This uses the decoupled build and run strategy to run the e2etests so that
we can arrange to run the tests against the real release packages produced
elsewhere in this workflow, rather than ones generated just in time by
the test harness.

The modifications to make-archive.sh here make it more consistent with its
originally-intended purpose of producing a harness for testing "real"
release executables. Our earlier compromise of making it include its own
terraform executable came from a desire to use that script as part of
manual cross-platform testing when we weren't yet set up to support
automation of those tests as we're doing here. That does mean, however,
that the terraform-e2etest package content must be combined with content
from a terraform release package in order to produce a valid contest for
running the tests.

We use a single job to cross-compile the test harness for all of the
supported platforms, because that build is relatively fast and so not
worth the overhead of matrix build, but then use a matrix build to
actually run the tests so that we can run them in a worker matching the
target platform.

We currently have access only to amd64 (x64) runners in GitHub Actions
and so for the moment this process is limited only to the subset of our
supported platforms which use that architecture.

For the moment this is just an experimental additional sidecar package
build process, separate from the one we really use for releases, so that
we can get some experience building in the GitHub Actions environment
before hopefully eventually switching to using the artifacts from this
process as the packages we'll release through the official release
channels.

It will react to any push to one of our release branches or to a release
tag by building official-release-like .zip, .deb, and .rpm packages, along
with Docker images, based on the content of the corresponding commit.

For the moment this doesn't actually produce _shippable_ packages because
in particular it doesn't know how to update our version/version.go file
to hard-code the correct version number. Once Go 1.18 is release and we've
upgraded to it we'll switch to using debug.ReadBuildInfo to determine
our version number at runtime and so no longer need to directly update
a source file for each release, but that functionality isn't yet available
in our current Go 1.17 release.