InfluxDB 2.0: The "/telegrafs" responses should have "orgID" instead of "OrgID" [area/api]

[bednar]

The Telegraf schema is defined as:

TelegrafRequest:
      type: object
      properties:
        name:
          type: string
        description:
          type: string
        agent:
          type: object
          properties:
            collectionInterval:
              type: integer
        plugins:
          type: array
          items:
            $ref: "#/components/schemas/TelegrafRequestPlugin"
        orgID:
          type: string

Telegraf:
      type: object
      allOf:
        - $ref: "#/components/schemas/TelegrafRequest"
        - type: object
          properties:
            id:
              type: string
              readOnly: true
            links:
              type: object
              readOnly: true
              example:
                self: "/api/v2/telegrafs/1"
                lables: "/api/v2/telegrafs/1/labels"
                owners: "/api/v2/telegrafs/1/owners"
                members: "/api/v2/telegrafs/1/members"
              properties:
                self:
                  $ref: "#/components/schemas/Link"
                labels:
                  $ref: "#/components/schemas/Link"
                members:
                  $ref: "#/components/schemas/Link"
                owners:
                  $ref: "#/components/schemas/Link"
            labels:
              readOnly: true
              $ref: "#/components/schemas/Labels"

but the response contains OrgID (uppercase)

-> POST 
-> http://127.0.0.1:9999/api/v2/telegrafs
-> {
	"name": "TelegrafConfig1559721891728-IT",
	"description": "test-config",
	"agent": {
		"collectionInterval": 1000
	},
	"plugins": [{
		"comment": "Output to Influx 2.0",
		"name": "influxdb_v2",
		"type": "output",
		"config": {
			"urls": ["http://127.0.0.1:9999"],
			"token": "$INFLUX_TOKEN",
			"organization": "my-org",
			"bucket": "my-bucket"
		}
	}, {
		"name": "cpu",
		"type": "input"
	}],
	"orgID": "03f5aa235c002000"
}

<- 201
<- Created
<- {
	"id": "03f5aa2ef3c02000",
	"OrgID": "03f5aa235c002000",
	"name": "TelegrafConfig1559721891728-IT",
	"description": "test-config",
	"agent": {
		"collectionInterval": 1000
	},
	"plugins": [{
		"name": "influxdb_v2",
		"type": "output",
		"comment": "Output to Influx 2.0",
		"config": {
			"urls": ["http://127.0.0.1:9999"],
			"token": "$INFLUX_TOKEN",
			"organization": "my-org",
			"bucket": "my-bucket"
		}
	}, {
		"name": "cpu",
		"type": "input",
		"comment": "",
		"config": {}
	}],
	"labels": [],
	"links": {
		"self": "/api/v2/telegrafs/03f5aa2ef3c02000",
		"labels": "/api/v2/telegrafs/03f5aa2ef3c02000/labels",
		"members": "/api/v2/telegrafs/03f5aa2ef3c02000/members",
		"owners": "/api/v2/telegrafs/03f5aa2ef3c02000/owners"
	}
}

caused by #13411, cc @kelwang

[bednar]

The telegrafConfigEncode should be change from:

type telegrafConfigEncode struct {
		ID          platform.ID                  `json:"id"`
		OrgID       platform.ID                  `json:"OrgID,omitempty"`
		...
}

to

type telegrafConfigEncode struct {
		ID          platform.ID                  `json:"id"`
		OrgID       platform.ID                  `json:"orgID,omitempty"`
		...
}