reportlab: canvas.getPageNumber() returns int (#14066)

stubs/reportlab/reportlab/pdfgen/canvas.pyi

@@ -186,7 +186,7 @@ class Canvas(_PDFColorSetter):
         kind: str = "URI",
         **kw,
     ) -> None: ...
-    def getPageNumber(self): ...
+    def getPageNumber(self) -> int: ...
     def save(self) -> None: ...
     def getpdfdata(self): ...
     def setPageSize(self, size: tuple[float, float]) -> None: ...