【Laravel】HTTPステータスコードの定数を使ってエラーを発生させる

# 目的
Laravelが用意しているHTTPステータスコードの定数を使用して、希望のエラーが発生させられるようにする。

# 使用例
`HTTP_UNPROCESSABLE_ENTITY`がHTTPステータスコードの定数
```php:TestRequest
    protected function failedValidation(Validator $validator)
    {
        throw new HttpResponseException(response()->json([
            'errors' => $validator->errors(),
        ], JsonResponse::HTTP_UNPROCESSABLE_ENTITY));
    }
```
Postmanで実行すると`422`が返ってくる。

![image.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/2784589/b21d6ac5-1310-0eb1-44d1-48c3ff8fc0c8.png)

# 何が用意されているか
`vendor/symfony/http-foundation/Response.php`を見ると分かる
```php:vendor/symfony/http-foundation/Response.php
   public const HTTP_CONTINUE = 100;
    public const HTTP_SWITCHING_PROTOCOLS = 101;
    public const HTTP_PROCESSING = 102;            // RFC2518
    public const HTTP_EARLY_HINTS = 103;           // RFC8297
    public const HTTP_OK = 200;
    public const HTTP_CREATED = 201;
    public const HTTP_ACCEPTED = 202;
    public const HTTP_NON_AUTHORITATIVE_INFORMATION = 203;
    public const HTTP_NO_CONTENT = 204;
    public const HTTP_RESET_CONTENT = 205;
    public const HTTP_PARTIAL_CONTENT = 206;
    public const HTTP_MULTI_STATUS = 207;          // RFC4918
    public const HTTP_ALREADY_REPORTED = 208;      // RFC5842
    public const HTTP_IM_USED = 226;               // RFC3229
    public const HTTP_MULTIPLE_CHOICES = 300;
    public const HTTP_MOVED_PERMANENTLY = 301;
    public const HTTP_FOUND = 302;
    public const HTTP_SEE_OTHER = 303;
    public const HTTP_NOT_MODIFIED = 304;
    public const HTTP_USE_PROXY = 305;
    public const HTTP_RESERVED = 306;
    public const HTTP_TEMPORARY_REDIRECT = 307;
    public const HTTP_PERMANENTLY_REDIRECT = 308;  // RFC7238
    public const HTTP_BAD_REQUEST = 400;
    public const HTTP_UNAUTHORIZED = 401;
    public const HTTP_PAYMENT_REQUIRED = 402;
    public const HTTP_FORBIDDEN = 403;
    public const HTTP_NOT_FOUND = 404;
    public const HTTP_METHOD_NOT_ALLOWED = 405;
    public const HTTP_NOT_ACCEPTABLE = 406;
    public const HTTP_PROXY_AUTHENTICATION_REQUIRED = 407;
    public const HTTP_REQUEST_TIMEOUT = 408;
    public const HTTP_CONFLICT = 409;
    public const HTTP_GONE = 410;
    public const HTTP_LENGTH_REQUIRED = 411;
    public const HTTP_PRECONDITION_FAILED = 412;
    public const HTTP_REQUEST_ENTITY_TOO_LARGE = 413;
    public const HTTP_REQUEST_URI_TOO_LONG = 414;
    public const HTTP_UNSUPPORTED_MEDIA_TYPE = 415;
    public const HTTP_REQUESTED_RANGE_NOT_SATISFIABLE = 416;
    public const HTTP_EXPECTATION_FAILED = 417;
    public const HTTP_I_AM_A_TEAPOT = 418;                                               // RFC2324
    public const HTTP_MISDIRECTED_REQUEST = 421;                                         // RFC7540
    public const HTTP_UNPROCESSABLE_ENTITY = 422;                                        // RFC4918
    public const HTTP_LOCKED = 423;                                                      // RFC4918
    public const HTTP_FAILED_DEPENDENCY = 424;                                           // RFC4918
    public const HTTP_TOO_EARLY = 425;                                                   // RFC-ietf-httpbis-replay-04
    public const HTTP_UPGRADE_REQUIRED = 426;                                            // RFC2817
    public const HTTP_PRECONDITION_REQUIRED = 428;                                       // RFC6585
    public const HTTP_TOO_MANY_REQUESTS = 429;                                           // RFC6585
    public const HTTP_REQUEST_HEADER_FIELDS_TOO_LARGE = 431;                             // RFC6585
    public const HTTP_UNAVAILABLE_FOR_LEGAL_REASONS = 451;                               // RFC7725
    public const HTTP_INTERNAL_SERVER_ERROR = 500;
    public const HTTP_NOT_IMPLEMENTED = 501;
    public const HTTP_BAD_GATEWAY = 502;
    public const HTTP_SERVICE_UNAVAILABLE = 503;
    public const HTTP_GATEWAY_TIMEOUT = 504;
    public const HTTP_VERSION_NOT_SUPPORTED = 505;
    public const HTTP_VARIANT_ALSO_NEGOTIATES_EXPERIMENTAL = 506;                        // RFC2295
    public const HTTP_INSUFFICIENT_STORAGE = 507;                                        // RFC4918
    public const HTTP_LOOP_DETECTED = 508;                                               // RFC5842
    public const HTTP_NOT_EXTENDED = 510;                                                // RFC2774
    public const HTTP_NETWORK_AUTHENTICATION_REQUIRED = 511;     
```
# 参考

https://qiita.com/miriwo/items/460b473131a77250f304