[HttpClient] Throw JsonException instead of TransportException on empty response in Response::toArray()

src/Symfony/Component/HttpClient/Response/ResponseTrait.php

@@ -137,7 +137,7 @@ trait ResponseTrait
     public function toArray(bool $throw = true): array
     {
         if ('' === $content = $this->getContent($throw)) {
-            throw new TransportException('Response body is empty.');
+            throw new JsonException('Response body is empty.');
         }
 
         if (null !== $this->jsonData) {

src/Symfony/Component/HttpClient/Tests/Response/MockResponseTest.php

@@ -35,6 +35,12 @@ class MockResponseTest extends TestCase
 
     public function toArrayErrors()
     {
+        yield [
+            'content' => '',
+            'responseHeaders' => [],
+            'message' => 'Response body is empty.',
+        ];
+
         yield [
             'content' => '{}',
             'responseHeaders' => ['content-type' => 'plain/text'],