Add useSWRImmutable helper hook

[b1rdex]

Some resources are immutable (or app should not revalidate their contents).

For now, I have to use it like this:

const { data: itemInfoData } = client.users.list.useSWR(
  {some: "params"},
  {
    revalidateIfStale: false,
    revalidateOnFocus: false,
    revalidateOnReconnect: false,
  },
);

Using the original SWR this could be simplified to

const { data: itemInfoData } = client.users.list.useSWRImmutable({some: 'params'});

Please consider adding this simple helper hook.