Tests: Update `testPublicRooms` and `testSearchPublicRooms` to follow HS response new behavior.
Tests: Update `testPublicRooms` and `testSearchPublicRooms` to follow HS response new behavior.

Note this new behavior has no impact on the app or upper layer.

matrix-org/matrix-ios-sdk,matrix-org/matrix-ios-sdk,matrix-org/matrix-ios-sdk,matrix-org/matrix-ios-sdk,matrix-org/matrix-ios-sdk