Link reference to PyModule_Exec added in python#139196

Author: encukou

Doc/c-api/import.rst

@@ -346,7 +346,7 @@ Importing Modules
    the same as for :c:func:`PyImport_AppendInittab`.
 
    On success, create and return a module object.
-   This module will not be initialized; call :c:func:`!PyModule_Exec`
+   This module will not be initialized; call :c:func:`PyModule_Exec`
    to initialize it.
    (Custom importers should do this in their
    :py:meth:`~importlib.abc.Loader.exec_module` method.)