message: Cover V4 protocol type
diff: @@ -478,7 +478,8 @@ pub fn update_agent_webhook(webhook_url: &str) -> VcxResult<()> {
  match settings::get_protocol_type() {
  settings::ProtocolTypes::V1 => update_agent_webhook_v1(&to_did, com_method)?,
  settings::ProtocolTypes::V2 |
  - settings::ProtocolTypes::V3 => update_agent_webhook_v2(&to_did, com_method)?,
  + settings::ProtocolTypes::V3 |
  + settings::ProtocolTypes::V4 => update_agent_webhook_v2(&to_did, com_method)?,
  }
  },
  Err(e) => warn!("Unable to update webhook (did you provide remote did in the config?): {}", e)
  