`Cannot read properties of null (reading 'oldState')` when joining and viewing room

### Steps to reproduce

1. `/join https://matrix.to/#/!PxFshrIDPHiPkrYzDj:gitter.im/$Cb2U5dY6HMvnlYaGeO5A0KsTEMVDwEXSrwBrbl8-IGM?via=gitter.im&via=matrix.org`
1. Notice that you're seemingly joined to the room but it's just blank
1. Notice the following error in the console:
```
Uncaught (in promise) TypeError: Cannot read properties of null (reading 'oldState')
at sync.ts:442:33
```
- Relevant code: https://github.com/matrix-org/matrix-js-sdk/blob/abc9c9dcb02fb1a1f8ec3da557a376580d8a4151/src/sync.ts#L438-L443

### Outcome

#### What did you expect?

Join and view room as expected

#### What happened instead?

Blank room view

### Operating system

Windows 10

### Browser information

Chrome Version 110.0.5481.78

### URL for webapp

https://develop.element.io/

### Application version

Element version: 2b779e5e4ab6-react-da7aa4055e04-js-abc9c9dcb02f Olm version: 3.2.12

### Homeserver

matrix.org

### Will you send logs?

Yes, https://github.com/matrix-org/element-web-rageshakes/issues/20092