docs: nomad scaling policy api

Prepare website for 0.11.0-beta1 release

doc: add a reminder about field order for diff comparisons

After spending hours re-learning this lesson more than once,
update the jobspec contribution guide with a reminder about
how to configure FieldDiff comparisons.

agent: prevent XSS by controlling Content-Type

[ci skip]

Co-Authored-By: Mahmood Ali <mahmood@hashicorp.com>

Some test fixes

Closes #7197 #7199

Note: Test coverage is limited to adapter and serializer unit tests. All
acceptance tests have been stubbed and all features have been manually
tested end-to-end.

This represents Phase 1 of #6993 which is the core workflow of CSI in
the UI. It includes a couple new pages for viewing all external volumes
as well as the allocations associated with each. It also updates
existing volume related views on job and allocation pages to handle both
Host Volumes and CSI Volumes.

Co-Authored-By: James Rasell <jrasell@users.noreply.github.com>

TestCSIPluginEndpoint_ACLNamespaceAlloc uses namespace features not
present in OSS.

TestStateStore_Indexes specifically tests for `nodes` index, but asserts
on the exact number of indexes present in the state.  This is fragile
and will break almost everytime we add a state index.

add missing changelog entry for 6975

health: detect failing tasks

Fix some flaky tests

Start collecting raw `go test -json` output to help with debugging odd
CI failures.

add changelog entries for 0.11.0

fix typo

update enterprise audit blurb

This connects Xterm.js to a Nomad exec websocket so people
can interact on clients via live sessions. There are buttons on
job, allocation, task group, and task detail pages that open a
popup that lets them edit their shell command and start a
session.

More is to come, as recorded in issues.

Support per-task RestartPolicy

more testing for scaling API