Run Argument Clinic: METH_VARARGS=>METH_FASTCALL

Issue #29286. Run Argument Clinic to get the new faster METH_FASTCALL calling
convention for functions using "boring" positional arguments.

Manually fix _elementtree: _elementtree_XMLParser_doctype() must remain
consistent with the clinic code.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index e2bdf08..5fbe56c 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -12453,14 +12453,14 @@
     chars: object = None
     /
 
-Return a copy of the string with leading and trailing whitespace removed.
+Return a copy of the string with leading and trailing whitespace remove.
 
 If chars is given and not None, remove characters in chars instead.
 [clinic start generated code]*/
 
 static PyObject *
 unicode_strip_impl(PyObject *self, PyObject *chars)
-/*[clinic end generated code: output=ca19018454345d57 input=385289c6f423b954]*/
+/*[clinic end generated code: output=ca19018454345d57 input=eefe24a1059c352b]*/
 {
     return do_argstrip(self, BOTHSTRIP, chars);
 }