fix: fix README.md example

Author: everysoftware

README.md

@@ -36,7 +36,7 @@ from fastlink.schemas import OAuth2Callback, OpenID
 
 app = FastAPI()
 
-oauth = GoogleSSO(
+sso = GoogleSSO(
     settings.google_client_id,
     settings.google_client_secret,
     "http://localhost:8000/callback",
@@ -45,15 +45,15 @@ oauth = GoogleSSO(
 
 @app.get("/login")
 async def login() -> RedirectResponse:
-    async with oauth:
-        url = await oauth.login_url()
+    async with sso:
+        url = await sso.login_url()
         return RedirectResponse(url=url)
 
 
 @app.get("/callback")
 async def callback(call: Annotated[OAuth2Callback, Depends()]) -> OpenID:
-    async with oauth:
-        return await oauth.callback(call)
+    async with sso:
+        return await sso.callback(call)
 
 ```