Remove initialData in nonce and session

It appears that in @tanstack/react-query v5 and up the query will not be fetched on mount if `initialData` is set. This means that the `ckSiweNonce` and `ckSiweSession` queries don't fire until their respective intervals have elapsed.

This commit removes the `initialData` for both of these queries in order to restore previous functionality.

packages/connectkit/src/siwe/SIWEProvider.tsx

@@ -48,14 +48,12 @@ export const SIWEProvider = ({
   const nonce = useQuery({
     queryKey: ['ckSiweNonce'],
     queryFn: () => siweConfig.getNonce(),
-    initialData: null,
     refetchInterval: nonceRefetchInterval,
   });
 
   const session = useQuery({
     queryKey: ['ckSiweSession'],
     queryFn: () => siweConfig.getSession(),
-    initialData: null,
     refetchInterval: sessionRefetchInterval,
   });