Some operators use very long group/task `shutdown_delay` settings to
safely drain network connections to their workloads after service
deregistration. But during incident response, they may want to cause
that drain to be skipped so they can quickly shed load.
Provide a `-no-shutdown-delay` flag on the `nomad alloc stop` and
`nomad job stop` commands that bypasses the delay. This sets a new
desired transition state on the affected allocations that the
allocation/task runner will identify during pre-kill on the client.
Note (as documented here) that using this flag will almost always
result in failed inbound network connections for workloads as the
tasks will exit before clients receive updated service discovery
information and won't be gracefully drained.
Alloc exec only works when task is passed as a flag and not an arg.
Alloc logs currently accepts either, but alloc signal and restart only
accept task as an arg. This adds -task as a flag to the other alloc
commands to make the cli UX consistent. If task is passed as a flag and
an arg, it ignores the arg.