add userVerificationMethods to API Payload

[pro4tlzz]

Fixes #2060

[pro4tlzz]

I can't test this because my free org doesn't have the capability to enable this feature flag.

The constraint looks like this. userVerificationMethods is an array of strings.

  constraints = [
    jsonencode({
      "possession" : {
        "required" : true,
        "authenticationMethods" : [
          {
            "key" : "okta_verify",
            "method" : "signed_nonce"
          }
        ],
        "hardwareProtection" : "REQUIRED",
        "phishingResistant" : "REQUIRED",
        "userPresence" : "REQUIRED",
        "userVerification" : "REQUIRED",
        "userVerificationMethods" : [
          "BIOMETRICS"
        ]
      }
      }
    )
  ]