changelog: manually add entry for #11793

deps: pty has new home

github.com/kr/pty was moved to github.com/creack/pty

Swap this dependency so we can upgrade to the latest version
and no longer need a replace directive.

deps: replace gzip handler

After swapping gzip handler to use the gorilla library, we
must account for a quirk in how zero/minimal length response
bodies are delivered.

The previous gzip handler was configured to compress all responses
regardless of size - even if the data was zero length or below the
network MTU. This behavior changed in [v1.1.0](https://github.com/nytimes/gziphandler/commit/c551b6c3b4b976eafa1a18220b5e21692784d8e2#diff-de723e6602cc2f16f7a9d85fd89d69954edc12a49134dab8901b10ee06d1879d)
which is why we could not upgrade.

The Nomad HTTP Client mutates the http.Response.Body object, making
a strong assumption that if the Content-Encoding header is set to "gzip",
the response will be readable via gzip decoder. This is no longer true
for the nytimes gzip handler, and is also not true for the gorilla gzip
handler.

It seems in practice this only makes a difference on the /v1/operator/license
endpoint which returns an empty response in OSS Nomad.

The fix here is to simply not wrap the response body reader if we
encounter an io.EOF while creating the gzip reader - indicating there
is no data to decode.

This has been pinned since the Go modules migration, because the
nytimes gzip handler was modified in version v1.1.0 in a way that
is no longer compatible.

Pretty sure it is this commit: https://github.com/nytimes/gziphandler/commit/c551b6c3b4b976eafa1a18220b5e21692784d8e2

Instead use handler.CompressHandler from gorilla, which is a web toolkit we already
make use of for other things.

deps: upgrade docker and runc

Merge release 1.2.4 branch

This PR upgrades
 - docker dependency to the latest tagged release (v20.10.12)
 - runc dependency to the latest tagged release (v1.0.3)

Docker does not abide by [semver](https://github.com/moby/moby/issues/39302), so it is marked +incompatible,
and transitive dependencies are upgrade manually.

Runc made three relevant breaking changes

 * cgroup manager .Set changed to accept Resources instead of Cgroup
   https://github.com/opencontainers/runc/commit/3f6594675675d4e88901c782462f56497260b1d2

 * config.Device moved to devices.Device
   https://github.com/opencontainers/runc/pull/2679

 * mountinfo.Mounted now returns an error if the specified path does not exist
   https://github.com/moby/sys/blob/mountinfo/v0.5.0/mountinfo/mountinfo.go#L16

Improves `nomad debug` error messages when contacting agents that do not
have /v1/agent/host endpoints (the endpoint was added in v0.12.0)

Part of #9568 and manually tested against Nomad v0.8.7.

Hopefully isRedirectError can be reused for more cases listed in #9568

changelog: add entry for #11848

feat:  add links to legend items in `allocation-summary`

The command line client sends a specific volume ID, but this isn't
enforced at the API level and we were incorrectly using a prefix match
for volume deregistration, resulting in cases where a volume with a
shorter ID that's a prefix of another volume would be deregistered
instead of the intended volume.

When the `volume deregister` or `volume detach` commands get an ID
prefix that matches multiple volumes, show the full length of the
volume IDs in the list of volumes shown so so that the user can select
the correct one.

The size of `stat_t` fields is architecture dependent, which was
reportedly causing a build failure on FreeBSD ARM7 32-bit
systems. This changeset matches the behavior we have on Linux.

When we copy the system DNS to a task's `resolv.conf`, we should set
the permissions as world-readable so that unprivileged users within
the task can read it.