Unblock 'check.method' in service validation. Add tests around making
sure this value gets plumbed through.

This PR continues work we've started on other test suites to use the native
golang test runner instead of the custom framework.

deps: update raft library

deps: update test package

Another attempt at resolving the flakey TestNomad_BootstrapExpect_NonVoter

Upgrading to v0.3.0 gives us the ability to add more context to test
case failures.

https://github.com/shoenig/test/pull/23

This test is a fairly trivial test of the agent RPC, but the test setup waits
for a short fixed window after the node starts to send the RPC. After looking at
detailed logs for recent test failures, it looks like the node registration for
the first node doesn't get a chance to happen before we make the RPC call. Use
`WaitForResultUntil` to give the test more time to run in slower test
environments, while allowing it to finish quickly if possible.

OOM detection under cgroups v2 is flaky under versions of `containerd` before
v1.6.3, but our `containerd` dependency is transitive on `moby/moby`, who have
not yet updated. Disable this test for cgroups v2 environments until we can
update the dependency chain.

The `golang.org/x/net/context` package was merged into the stdlib as of go
1.7. Update the imports to use the identical stdlib version. Clean up import
blocks for the impacted files to remove unnecessary package aliasing.

website: enable setting custom tool for launching website dev container

When working in a podman environment, it's nice to just run the website
development container using podman.

fix alloc working directory path

* ui: add namespace filter feature

ui:  add namespace filtering to variables.index

test:  namespace filter

refact:  fix action in template

ui:  move data fetching and query param logic to

ui:  controller query parameter logic

ui:  prevent  from forwarding query param

ui:  create variables controller

refact:  use dependency injection for controlling parent qp

chore: clean-up reset in  route

chore:  clean-up reset in  route

* ui:  add namespace filter to secure var form (#13629)

ui:  update variable factory to accept namespaces

refact:  update  api to accept disabled

ui:  add namespace setting logic to form

refact:  remove debugger

refact:  get correct selectors for

ui:  move data loading to namespace-filter component

chore:  prettify template

ui: update factory to handle namespace setting

refact:  remove inline styling for grid class

* ui:  fix placement of filter in `SecureVariablesForm` ...

cleanup: remove unneeded darwin lib

When we delete a namespace, we check to ensure that there are no non-terminal
jobs or CSI volume, which also covers evals, allocs, etc. Secure variables are
also namespaces, so extend this check to them as well.

cleanup: use constants for on_update values

When we delete a namespace, we check to ensure that there are no non-terminal
jobs, which effectively covers evals, allocs, etc. CSI volumes are also
namespaced, so extend this check to cover CSI volumes.

client: add support for checks in nomad services

servicedisco: ensure service uniqueness in job validation 

client: use test timeouts for network fingerprinters in dev mode

Workload identities grant implicit access to policies, and operators
will not want to craft separate policies for each invocation of a
periodic or dispatch job. Use the parent job's ID as the JobID claim.

The search RPC used a placeholder policy for searching within the secure
variables context. Now that we have ACL policies built for secure variables, we
can use them for search. Requires a new loose policy for checking if a token has
any secure variables access within a namespace, so that we can filter on
specific paths in the iterator.

Most of our objects use int64 timestamps derived from `UnixNano()` instead of
`time.Time` objects. Switch the keyring metadata to use `UnixNano()` for
consistency across the API.

To discourage accidentally DoS'ing the cluster with secure variables
data, we're providing a very low limit to the maximum size of a given
secure variable. This currently matches the limit for dispatch
payloads.

In future versions, we may increase this limit or make it
configurable, once we have better metrics from real-world operators.

Document the secure variables keyring commands, document the aliased
gossip keyring commands, and note that the old gossip keyring commands
are deprecated.

Return 429 response on HTTP max connection limit. Instead of silently closing
the connection, return a `429 Too Many Requests` HTTP response with a helpful
error message to aid debugging when the connection limit is unintentionally
reached.

Set a 10-millisecond write timeout and rate limiter for connection-limit 429
response to prevent writing the HTTP response from consuming too many server
resources.

Add `nomad.agent.http.exceeded metric` counting the number of HTTP connections
exceeding concurrency limit.