Fix empty iter error message in min/max

Change misleading "empty sequence" to "empty iterable" in builtins.min/max.
Update corresponding test to be more specific and match the error string.

Author: Nnarol

Lib/test/test_builtin.py

@@ -1031,7 +1031,11 @@ def test_max(self):
             max()
 
         self.assertRaises(TypeError, max, 42)
-        self.assertRaises(ValueError, max, ())
+        with self.assertRaisesRegex(
+            ValueError,
+            r'max\(\) iterable argument is empty'
+        ):
+            max(())
         class BadSeq:
             def __getitem__(self, index):
                 raise ValueError
@@ -1090,7 +1094,11 @@ def test_min(self):
             min()
 
         self.assertRaises(TypeError, min, 42)
-        self.assertRaises(ValueError, min, ())
+        with self.assertRaisesRegex(
+            ValueError,
+            r'min\(\) iterable argument is empty'
+        ):
+            min(())
         class BadSeq:
             def __getitem__(self, index):
                 raise ValueError

Python/bltinmodule.c

@@ -1786,7 +1786,7 @@ min_max(PyObject *args, PyObject *kwds, int op)
             maxitem = defaultval;
         } else {
             PyErr_Format(PyExc_ValueError,
-                         "%s() arg is an empty sequence", name);
+                         "%s() iterable argument is empty", name);
         }
     }
     else