Signond: fix cancellation of idle requests
Signond: fix cancellation of idle requests

When the request being cancelled was the first one in the queue, the
code assumed that it was also active, meaning that it would wait for a
reply from the plugin. However, in some situations, it may well occur
that the first request in the queue is not active, and in such case it
should be removed immediately without waiting for the plugin's reply
(which would never arrive).

plotters/accounts-sso.signond,plotters/accounts-sso.signond,plotters/accounts-sso.signond