fix: introduce system env var, remove debug mode (#4658)

* fix: introduce system env var

* docs

* docs

lib/http.php

@@ -23,12 +23,10 @@ class HttpException extends \Exception
     public static function fromResponse(Response $response, string $url): HttpException
     {
         $message = sprintf(
-            '%s resulted in %s %s %s',
+            '%s resulted in %s %s',
             $url,
             $response->getCode(),
-            $response->getStatusLine(),
-            // If debug, include a part of the response body in the exception message
-            Debug::isEnabled() ? mb_substr($response->getBody(), 0, 500) : '',
+            $response->getStatusLine()
         );
         if (CloudFlareException::isCloudFlareResponse($response)) {
             return new CloudFlareException($message, $response->getCode(), $response);