Add -json and -t flag for nomad acl token create command

[dttung2905]

Hi team,

This PR aims to add -json and -t flag for nomad acl token create command. This is related to issue #15894

Example output:

• With -json flag

❯ nomad acl token create -type="management" -global=true \
  -name="Cluster A Replication Token" \
  -token="abcxyz" -ttl=10m -json
{
    "AccessorID": "83a61305-15c2-c78a-1c59-75c44afa7a13",
    "CreateIndex": 927,
    "CreateTime": "2023-02-04T09:39:33.710007669Z",
    "ExpirationTTL": 600000000000,
    "ExpirationTime": "2023-02-04T09:49:33.710007669Z",
    "Global": true,
    "ModifyIndex": 927,
    "Name": "Cluster A Replication Token",
    "Policies": null,
    "Roles": null,
    "SecretID": "6d23da6a-677d-c7b9-02ac-f1c41ad5f5d0",
    "Type": "management"
}

• With -t flag

❯ nomad acl token create -type="management" -global=true \
  -name="Cluster A Replication Token" \
  -token="abcxyz" -ttl=10m -t='{{ .ExpirationTTL }}'

10m0s

[jrasell]

Hi @dttung2905 and thanks for raising this; it's looking great. I've made a couple of very minor suggestions inline. I also wonder if it would be possible to update the tests added slightly, in particular when testing the JSON flag to check we have valid JSON returned in the output writer. Thanks again!

[dttung2905]

Hi @jrasell. Thanks for the super quick review. I didn't check the semantic of JSON output i.e. all KV pairs because I think its abit uncessary. Hence, I have only added a check for a proper JSON formatted output. Please let me know what you think on this 🙏

[jrasell]

Thanks for the updates @dttung2905 and LGTM! The unmarshal testing trick is something I have used elsewhere, so it's nice to see others see this as an approach to take. Thanks!