added missing tests for new bolt version

src/protocol/V5_6.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace Bolt\protocol;
+
+/**
+ * Class Protocol version 5.4
+ *
+ * @author Michal Stefanak
+ * @link https://github.com/neo4j-php/Bolt
+ * @see https://www.neo4j.com/docs/bolt/current/bolt/message/
+ * @package Bolt\protocol
+ */
+class V5_6 extends AProtocol
+{
+    use \Bolt\protocol\v5\AvailableStructures;
+    use \Bolt\protocol\v5_1\ServerStateTransition;
+
+    use \Bolt\protocol\v1\ResetMessage;
+
+    use \Bolt\protocol\v3\RunMessage;
+    use \Bolt\protocol\v3\BeginMessage;
+    use \Bolt\protocol\v3\CommitMessage;
+    use \Bolt\protocol\v3\RollbackMessage;
+    use \Bolt\protocol\v3\GoodbyeMessage;
+
+    use \Bolt\protocol\v4\PullMessage;
+    use \Bolt\protocol\v4\DiscardMessage;
+
+    use \Bolt\protocol\v4_4\RouteMessage;
+
+    use \Bolt\protocol\v5_1\LogonMessage;
+    use \Bolt\protocol\v5_1\LogoffMessage;
+
+    use \Bolt\protocol\v5_3\HelloMessage;
+
+    use \Bolt\protocol\v5_4\TelemetryMessage;
+}

tests/protocol/V5_6Test.php

@@ -0,0 +1,20 @@
+<?php
+
+use Bolt\protocol\V5_6;
+
+/**
+ * Class V5_6Test
+ *
+ * @author Michal Stefanak
+ * @link https://github.com/neo4j-php/Bolt
+ * @package Bolt\tests\protocol
+ */
+class V5_6Test extends \Bolt\tests\protocol\ProtocolLayer
+{
+    public function test__construct(): V5_6
+    {
+        $cls = new V5_6(1, $this->mockConnection());
+        $this->assertInstanceOf(V5_6::class, $cls);
+        return $cls;
+    }
+}