Merge branch '5.1' into 5.2

* 5.1:
  [Notifier] Fix parsing Dsn with empty user/password
  Remove void return type from test methods
  [Notifier] Use assertSame()

Tests/Transport/AmazonSqsIntegrationTest.php

@@ -21,7 +21,7 @@
  */
 class AmazonSqsIntegrationTest extends TestCase
 {
-    public function testConnectionSendToFifoQueueAndGet(): void
+    public function testConnectionSendToFifoQueueAndGet()
     {
         if (!getenv('MESSENGER_SQS_FIFO_QUEUE_DSN')) {
             $this->markTestSkipped('The "MESSENGER_SQS_FIFO_QUEUE_DSN" environment variable is required.');
@@ -30,7 +30,7 @@ public function testConnectionSendToFifoQueueAndGet(): void
         $this->execute(getenv('MESSENGER_SQS_FIFO_QUEUE_DSN'));
     }
 
-    public function testConnectionSendAndGet(): void
+    public function testConnectionSendAndGet()
     {
         if (!getenv('MESSENGER_SQS_DSN')) {
             $this->markTestSkipped('The "MESSENGER_SQS_DSN" environment variable is required.');