This PR adds a set of tests to the Consul test suite for testing
Nomad OSS's behavior around setting Consul Namespace on groups,
which is to ignore the setting (as Consul Namespaces are currently
an Enterprise feature).
Tests are generally a reduced facsimile of existing tests, modified
to check behavior of when group.consul.namespace is set and not set.
Verification is oriented around what happens in Consul; the in-depth
functional correctness of these features is left to the original tests.
Nomad ENT will get its own version of these tests in `namespaces_ent.go`.
Deflake namespace e2e test by only asserting on jobs related to the
namespace tests. During our e2e tests, some left over jobs (e.g.
prometheus) are left running while being shutdown and cause the test to
fail.
Assert that deregistering a volume works without errors following a volume
reap. Use CLI helpers where feasible to exercise CSI command line. Dump plugin
allocation logs on deregistration failures for debugging purposes.
Exercises host volume and Docker volume functionality for the `exec` and `docker`
task driver, particularly around mounting locations within the container and
how this can be used with `template`.
The CLI helpers in the rescheduling test were intended for shared use, but
until some other tests were written we didn't want to waste time making them
generic. This changeset refactors them and adds some new helpers associated
with the node drain tests (under separate PR).
