fix: change read once member data type

Author: uerceg

Assets/Adjust/Unity/AdjustConfig.cs

@@ -62,7 +62,7 @@ public class AdjustConfig
         internal string preinstallFilePath;
         internal bool? finalAndroidAttributionEnabled;
         internal string fbAppId;
-        internal bool readDeviceInfoOnceEnabled;
+        internal bool? readDeviceInfoOnceEnabled;
         // iOS specific members
         internal bool? allowAdServicesInfoReading;
         internal bool? allowIdfaReading;