api/ui: alloc stop incorrectly documented

The Nomad docs detail the alloc stop CLI command as allowing "a user to perform an in-place restart of an entire allocation or individual task". The Nomad UI details the alloc stop that "This will reschedule the allocation on a different client".

These are both incorrect as stopping an allocation will result in a rescheduling of the allocation which can either be on the same node, or a different node, depending on the scheduling outcome and parameters.

We should come up with common wording and update these two locations along with the nomad alloc stop CLI help output. The Nomad CLI has the following help output which seems accurate:

  Stop an existing allocation. This command is used to signal a specific alloc
  to shut down. When the allocation has been shut down, it will then be
  rescheduled.

Start by comparing the alloc stop CLI documentation, the Nomad UI allocation-stop text, and the nomad alloc stop help output described in the issue. Align all three locations so they state that stopping an allocation shuts it down and reschedules it, potentially on the same or a different client, then verify the wording is consistent.