Fix checks to show prompt to start new chats
Fix checks to show prompt to start new chats

We compared the length of the list rooms but not historical or favourite.

Caught by new version of typescript when I tried to upgrade.

matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk