pythongh-97696: Remove redundant #include (python#104216)

Remove "#include cpython/context.h"` from `_asynciomodule.c`.

It's already included in `Python.h`.

Author: jbower-fb

Modules/_asynciomodule.c

@@ -8,7 +8,6 @@
 #include "pycore_runtime_init.h"  // _Py_ID()
 #include "pycore_moduleobject.h"  // _PyModule_GetState()
 #include "structmember.h"         // PyMemberDef
-#include "cpython/context.h"
 #include <stddef.h>               // offsetof()