Add PurpleAccount::error property and remove "account-error-changed" and "account-status-changing" signals.
Review Request #2036 — Created Nov. 5, 2022 and submitted
Also sorted the account signal changes in ChangeLog.API. The account-error-changed signal is easily replaced by the notify signal for the new property, and account-status_changing wasn't used by anything.
Used the account actions of the demo protocol plugin to disconnect the account without issue.