message: schema: simplify tests
diff: -use std::collections::{BTreeMap, HashMap};
  +use std::collections::HashMap;
  -use cosmwasm_schema::{schema_for, Api, IDL_VERSION};
  +use cosmwasm_schema::{generate_api, schema_for, Api, QueryResponses, IDL_VERSION};
  use schemars::JsonSchema;
  use serde::{Deserialize, Serialize};
  use serde_json::Value;
  @@ -19,9 +19,10 @@ pub enum ExecuteMsg {
  Mint { amount: u128 },
  }
  -#[derive(Serialize, Deserialize, Clone, Debug, PartialEq, JsonSchema)]
  +#[derive(Serialize, Deserialize, Clone, Debug, PartialEq, JsonSchema, QueryResponses)]
  #[serde(rename_all = "snake_case")]
  pub enum QueryMsg {
  + #[returns(u128)]
  Balance { account: String },
  }
  @@ -39,15 +40,14 @@ pub struct MigrateMsg {
  #[test]
  fn test_basic_structure() {
  - let api_str = Api {
  - contract_name: "test".to_string(),
  - contract_version: "0.1.0".to_string(),
  - instantiate: schema_for!(InstantiateMsg),
  - execute: Some(schema_for!(ExecuteMsg)),
  - query: Some(schema_for!(QueryMsg)),
  - migrate: Some(schema_for!(MigrateMsg)),
  - sudo: Some(schema_for!(SudoMsg)),
  - responses: Some(BTreeMap::from([("balance".to_string(), schema_for!(u128))])),
  + let api_str = generate_api! {
  + name: "test",
  + version: "0.1.0",
  + instantiate: InstantiateMsg,
  + query: QueryMsg,
  + execute: ExecuteMsg,
  + sudo: SudoMsg,
  + migrate: MigrateMsg,
  }
  .render()
  .to_string()
  @@ -81,15 +81,9 @@ fn test_basic_structure() {
  #[test]
  fn test_query_responses() {
  - let api_str = Api {
  - contract_name: "test".to_string(),
  - contract_version: "0.1.0".to_string(),
  - instantiate: schema_for!(InstantiateMsg),
  - execute: Some(schema_for!(ExecuteMsg)),
  - query: Some(schema_for!(QueryMsg)),
  - migrate: None,
  - sudo: None,
  - responses: Some(BTreeMap::from([("balance".to_string(), schema_for!(u128))])),
  + let api_str = generate_api! {
  + instantiate: InstantiateMsg,
  + query: QueryMsg,
  }
  .render()
  .to_string()
  