MXRestClient: Make publicRooms still use the old "GET" API if there is no params (It does not required an access token).
MXRestClient: Make publicRooms still use the old "GET" API if there is no params (It does not required an access token).

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