Update engine-test-data to v3.4.1

Co-authored-by: Claude <noreply@anthropic.com>

Author: emyller

.gitmodules

@@ -1,4 +1,4 @@
 [submodule "tests/Engine/EngineTests/EngineTestData"]
 	path = tests/Engine/EngineTests/EngineTestData
 	url = git@github.com:Flagsmith/engine-test-data.git
-	tag = v3.3.0
+	tag = v3.4.1

src/Engine/Utils/Types/Context/EvaluationContext.php

@@ -30,7 +30,7 @@ public static function fromJsonObject($jsonContext)
 
         if (!empty($jsonContext->identity)) {
             $context->identity = new IdentityContext();
-            $context->identity->key = $jsonContext->identity->key;
+            $context->identity->key = $jsonContext->identity->key ?? null;
             $context->identity->identifier = $jsonContext->identity->identifier;
             $context->identity->traits = (array) ($jsonContext->identity->traits ?? []);
         }

src/Engine/Utils/Types/Context/IdentityContext.php

@@ -4,7 +4,7 @@
 
 class IdentityContext
 {
-    /** @var string */
+    /** @var ?string */
     public $key;
 
     /** @var string */