[HttpFoundation] Fix typo in exception message

Author: carlos-ea

Request.php

@@ -1573,7 +1573,7 @@ public function getContent(bool $asResource = false)
     public function toArray()
     {
         if ('' === $content = $this->getContent()) {
-            throw new JsonException('Response body is empty.');
+            throw new JsonException('Request body is empty.');
         }
 
         try {

Tests/RequestTest.php

@@ -1260,7 +1260,7 @@ public function testToArrayEmpty()
     {
         $req = new Request();
         $this->expectException(JsonException::class);
-        $this->expectExceptionMessage('Response body is empty.');
+        $this->expectExceptionMessage('Request body is empty.');
         $req->toArray();
     }