To check total run time

The github actions cache cannot be modified in parallel, so we copy it
into a workflow artifact and then merge the artifacts together at the
end

in make as we do in bazel

Update with `make -C deps/rabbit
../../.github/workflows/test-rabbit.yaml`

`make actions-workflows` to update

If a new plugin is added, update TESTED_PLUGINS in Makefile and
test-make.yaml workflow accordingly

It turns out github actions won't let you template a matrix value into
the 'uses' of a job, so we have to template out the file

If there is a cache hit, there is never a save. Therefore, we need to
always miss on the first run attempt, falling back hopefully to the
previous run.

So that github actions does not report it as an errored workflow, when
it is only a template

so we can see what fails

since the test suite in rabbitmq_prometheus invokes test-build, it
ends up wiping out any copies of the module. Links seem to be the most
natural workaround, as the module depends on the federation header and
therefore can't be easily moved to rabbit_ct_helpers

It turns out that actions workflow artifacts are visible to everyone,
so injected credentials would be leaked via the test logs. Therefore
we just skip them (they still run in the bazel workflows where the
logs are protected).

otherwise it's stale

therefore all dimensions of the matrix must be included in the key,
otherwise the first to finish within the matrix, wins

Technically this is a workaround - dialyzer should not be checking the
khepri source in this case

Since we apparently hit a workflow size limit