Bug: couchdb: couchdb can not use account login

[fbewivpjsbsby]

When use username:password@server can not login.

When use couchdb 3.3.2, couchdbCredentials page can not open in password incorrect.

_session report 400 {"error":"bad_request","reason":"request body must contain a username"}, but
https://github.com/benweet/stackedit/blob/master/src/services/providers/helpers/couchdbHelper.js#L10
show only 401 can open page.

I see _session post body is blank.
https://github.com/benweet/stackedit/blob/master/src/components/modals/providers/CouchdbCredentialsModal.vue#L26