fix 日志打印错误

app/src/main/java/com/doverfuelingsolutions/issp/utils/log/DFSLogger.kt

@@ -69,7 +69,8 @@ object DFSLogger {
     }
 
     private fun stringify(content: Any?): String = when (content) {
-        is Iterable<*> -> content.joinToString { it.toString() }
+        is String -> content
+        is Iterable<*> -> content.joinToString { stringify(it) }
         is Throwable -> getFullStackTrace(content)
         else -> gson.toJson(content)
     }