Rename _PyObject_FastCall() to _PyObject_FastCallDict()

Issue #27809:

* Rename _PyObject_FastCall() function to _PyObject_FastCallDict()
* Add _PyObject_FastCall(), _PyObject_CallNoArg() and _PyObject_CallArg1()
  macros calling _PyObject_FastCallDict()
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index be8e164..c170bd5 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -380,7 +380,7 @@
     stack[2] = (arg != NULL) ? arg : Py_None;
 
     /* call the Python-level function */
-    result = _PyObject_FastCall(callback, stack, 3, NULL);
+    result = _PyObject_FastCall(callback, stack, 3);
 
     PyFrame_LocalsToFast(frame, 1);
     if (result == NULL) {
@@ -2122,7 +2122,7 @@
     if (writer == NULL)
         goto error;
 
-    result = _PyObject_FastCall(writer, &unicode, 1, NULL);
+    result = _PyObject_CallArg1(writer, unicode);
     if (result == NULL) {
         goto error;
     } else {