Fix constraints in the Zenject.Editor.TestFramework assembly

Author: arimger

Assets/Package/Plugins/Zenject/Editor/TestFramework/Zenject.Editor.TestFramework.asmdef

@@ -14,7 +14,9 @@
         "nunit.framework.dll"
     ],
     "autoReferenced": false,
-    "defineConstraints": [],
+    "defineConstraints": [
+        "UNITY_INCLUDE_TESTS"
+    ],
     "versionDefines": [],
     "noEngineReferences": false
 }