fix: on /rqlio, csrf is activaved only on multipart/form-data
POST for application/json are safe from csrf but not multipart/form-data. CSRF protection is thus disabled on application/json (no matter the authentications method). For multipart/form-data, there are 3 usecases: 1. multipart/form-data authenticated by cookies (webrowser), this requires csrf and this is handled by MultipartRqlIOController. 2. multipart/form-data anon user, this does not require csrf and this in handled by AnonMultipartRqlIOController 3. multipart/form-data authenticated with authorization, this does not requires csrf as there is an authentification. This is not handled here but in signed-request that implements the authentification.