Test stop of server task.

Author: janiversen

API_changes.rst

@@ -5,10 +5,11 @@ PyModbus - API changes.
 -------------
 Version 3.1.0
 -------------
-Added --host to client_* examples, to allow easier use.
-unit= in client calls are no longer converted to slave=, but raises a runtime exception.
-Added missing client calls (all standard request are not available as methods).
-client.mask_write_register() changed parameters.
+- Added --host to client_* examples, to allow easier use.
+- unit= in client calls are no longer converted to slave=, but raises a runtime exception.
+- Added missing client calls (all standard request are not available as methods).
+- client.mask_write_register() changed parameters.
+- server classes no longer accept reuse_port= (the socket do not accept it)
 
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 Version 3.0.1 / 3.0.2