Fixed upload path

src/kakigoori/__init__.py

@@ -18,7 +18,7 @@ class Kakigoori:
     async def upload(self, image: bytes) -> tuple[str, str]:
         async with aiohttp.ClientSession() as session:
             async with session.post(
-                urllib.parse.urljoin(self.base_url, "/upload/"),
+                urllib.parse.urljoin(self.base_url, "/upload"),
                 headers={"Authorization": f"{self.api_key}"},
                 data={"file": BytesIO(image)},
             ) as response: