[BUG] fields.info not camelCase

[xarem]

Describe the bug

Similar to #3241

fields.info is still PascalCase

To Reproduce

vcsim -api-version 8.0 -dc 0 -l :8989 &
export GOVC_URL=https://user:pass@172.17.0.2:8989/sdk GOVC_SIM_PID=10
export GOVC_INSECURE=true

govc fields.add -type=Folder folder-test
govc datacenter.create test-dc
govc cluster.create test-cluster
govc cluster.add -hostname test-host -username user -password pass -noverify
govc datastore.create -type local -name test-ds -path /tmp 'test-cluster/*'
govc vm.create -net="VM Network" -m=4096 -c=1 -g=ubuntu -disk=40G -folder=/test-dc/vm test-vm
govc fields.set folder-test "Hello world" /test-dc/vm/test-vm
govc fields.info -json /test-dc/vm/test-vm

Result

{
  "Info": [
    {
      "Object": {
        "type": "VirtualMachine",
        "value": "vm-22"
      },
      "Path": "/test-dc/vm/test-vm",
      "Name": "test-vm",
      "Key": "folder-test",
      "Value": "Hello world"
    }
  ]
}

Expected behavior

{
  "info": [
    {
      "object": {
        "type": "VirtualMachine",
        "value": "vm-22"
      },
      "path": "/test-dc/vm/test-vm",
      "name": "test-vm",
      "key": "folder-test",
      "value": "Hello world"
    }
  ]
}

Affected version

v0.31.0