Added some missing parameter annotations and type arguments detected by pyright. (#5061)

Co-authored-by: Eric Traut <erictr@microsoft.com>

stubs/python-dateutil/dateutil/_common.pyi

@@ -5,7 +5,7 @@ _T = TypeVar("_T")
 class weekday(object):
     def __init__(self, weekday: int, n: Optional[int] = ...) -> None: ...
     def __call__(self: _T, n: int) -> _T: ...
-    def __eq__(self, other) -> bool: ...
+    def __eq__(self, other: object) -> bool: ...
     def __repr__(self) -> str: ...
     def __hash__(self) -> int: ...
     weekday: int

stubs/python-dateutil/dateutil/relativedelta.pyi

@@ -88,7 +88,7 @@ class relativedelta(object):
     def __nonzero__(self) -> bool: ...
     def __mul__(self: _SelfT, other: SupportsFloat) -> _SelfT: ...
     def __rmul__(self: _SelfT, other: SupportsFloat) -> _SelfT: ...
-    def __eq__(self, other) -> bool: ...
+    def __eq__(self, other: object) -> bool: ...
     def __ne__(self, other: object) -> bool: ...
     def __div__(self: _SelfT, other: SupportsFloat) -> _SelfT: ...
     def __truediv__(self: _SelfT, other: SupportsFloat) -> _SelfT: ...