gh-70647: Raise a more informative error for when date is out of range (GH-131335)

More informative error messages mean less debugging what went wrong.

Modules/_datetimemodule.c

@@ -664,7 +664,8 @@ check_date_args(int year, int month, int day)
     int dim = days_in_month(year, month);
     if (day < 1 || day > dim) {
         PyErr_Format(PyExc_ValueError,
-                     "day must be in 1..%d, not %d", dim, day);
+                     "day %i must be in range 1..%d for month %i in year %i",
+                     day, dim, month, year);
         return -1;
     }
     return 0;