Add separator to exception messages (#346)

* Add separator to exception messages

* Updated failing test to reflect new code changes.

Author: ash-jc-allen

src/Messages/ExceptionErrorHandler.php

@@ -44,9 +44,9 @@ public function __invoke(ResponseInterface $response, RequestInterface $request)
         }
 
         if ($statusCode >= 500 && $statusCode <= 599) {
-            throw new ClientException\Server($responseBody['title'] . $responseBody['detail']);
+            throw new ClientException\Server($responseBody['title'] . ': ' . $responseBody['detail']);
         }
 
-        throw new ClientException\Request($responseBody['title'] . $responseBody['detail']);
+        throw new ClientException\Request($responseBody['title'] . ': ' . $responseBody['detail']);
     }
 }

test/Messages/ClientTest.php

@@ -634,7 +634,7 @@ public function testCanSendViberText(): void
     public function testThrowsRequestErrorOnBadRequest(): void
     {
         $this->expectException(Client\Exception\Request::class);
-        $this->expectErrorMessage('The request body did not contain valid JSONUnexpected character (\'"\' (code 34)): was expecting comma to separate Object entries');
+        $this->expectErrorMessage('The request body did not contain valid JSON: Unexpected character (\'"\' (code 34)): was expecting comma to separate Object entries');
 
         $payload = [
             'to' => '447700900000',