addeed thread_priority to the documentation

include/realtime_tools/async_function_handler.hpp

@@ -78,6 +78,7 @@ class AsyncFunctionHandler
  * @param async_function Function that will be called asynchronously
  * @param trigger_predicate Predicate function that will be called to check if the async update
  * method should be triggered.
+ * @param thread_priority Priority of the async update thread
  *
  * \note The parsed trigger_predicate should be free from any concurrency issues. It is expected
  * to be both thread-safe and reentrant.