itertools: Improve precision of itertools.product types when called with 7 or more arguments (#11163)

Author: winestone

stdlib/itertools.pyi

@@ -220,21 +220,7 @@ class product(Iterator[_T_co]):
         __iter6: Iterable[_T6],
     ) -> product[tuple[_T1, _T2, _T3, _T4, _T5, _T6]]: ...
     @overload
-    def __new__(
-        cls,
-        __iter1: Iterable[Any],
-        __iter2: Iterable[Any],
-        __iter3: Iterable[Any],
-        __iter4: Iterable[Any],
-        __iter5: Iterable[Any],
-        __iter6: Iterable[Any],
-        __iter7: Iterable[Any],
-        *iterables: Iterable[Any],
-    ) -> product[tuple[Any, ...]]: ...
-    @overload
-    def __new__(cls, *iterables: Iterable[_T1], repeat: int) -> product[tuple[_T1, ...]]: ...
-    @overload
-    def __new__(cls, *iterables: Iterable[Any], repeat: int = ...) -> product[tuple[Any, ...]]: ...
+    def __new__(cls, *iterables: Iterable[_T1], repeat: int = 1) -> product[tuple[_T1, ...]]: ...
     def __iter__(self) -> Self: ...
     def __next__(self) -> _T_co: ...