upgrading from v9/v10 to v12 leads to no rights for extensions

### Description

When you upgrade a room from v10 to v12 and then want to add an extension, e.g feeds you get the error message:
you don’t have permission to add some extensions to the room

### Steps to reproduce

/upgraderoom 10/v9
/upgraderoom 12
Try to add an Extension

### Homeserver

matrix.org/tchncs.de

### Synapse Version

1.136.0

### Anything else that would be useful to know?

Workarround after upgrading to v12:
[BE CAREFULL AND HAVE A 2ND ADMIN ACCOUNT IN THE ROOM](https://github.com/element-hq/synapse/issues/18810)
```
/upgraderoom v6
/upgraderoom v12
```

€dit: The workarround didn't work vor me for a room which was v9 🤔

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upgrading from v12 to v12 don't help!

€dit: I experienced this bug for v6,v9,v10