fix encoding/decoding tags for api.Task (#7620)
fix encoding/decoding tags for api.Task (#7620)

When `nomad job inspect` encodes the response, if the decoded JSON
from the API doesn't exactly match the API struct, the field value
will be omitted even if it has a value. We only want the JSON struct
tag to `omitempty`.
dvusboy/nomad,burdandrei/nomad,hashicorp/nomad,hashicorp/nomad,hashicorp/nomad,dvusboy/nomad,dvusboy/nomad,burdandrei/nomad,burdandrei/nomad,hashicorp/nomad,burdandrei/nomad,dvusboy/nomad,burdandrei/nomad,hashicorp/nomad,dvusboy/nomad,dvusboy/nomad,dvusboy/nomad,hashicorp/nomad,burdandrei/nomad,burdandrei/nomad