Fix an issue with react router and dev mode for the /new route. (#4063)

In dev mode you get the below error when visiting the `/new` route. The
route seems to be hit several times before finally navigating to the
correct room. This seems to solve it.


![image](https://github.com/tldraw/tldraw/assets/2523721/cbc4a6ef-9168-414f-b07a-b4d6af6d7256)

### Change type

- [x] `bugfix`
- [ ] `improvement`
- [ ] `feature`
- [ ] `api`
- [ ] `other`


### Release notes

- Fixed a but with navigating to `/new`.

apps/dotcom/src/pages/new.tsx

@@ -24,6 +24,11 @@ const { loader, useData } = defineLoader(async (_args) => {
 
 export { loader }
 
+// Using this directly in Navigate caused a "Maximum update depth exceeded" error in dev
+const state = {
+	shouldOpenShareMenu: true,
+}
+
 export function Component() {
 	const data = useData()
 	if (!data)
@@ -36,13 +41,5 @@ export function Component() {
 			/>
 		)
 
-	return (
+	return <Navigate replace state={state} to={`/${ROOM_PREFIX}/${data.slug}`} />
-		<Navigate
-			replace
-			state={{
-				shouldOpenShareMenu: true,
-			}}
-			to={`/${ROOM_PREFIX}/${data.slug}`}
-		/>
-	)
 }