fix automatic status update trigger (פניה חדשה --> בטיפול)

1. On the first intake talk, the agent starts running through the thread.
2. After 2-3 questions the agent clicks on the "חזרה לרשימת הפונים" link.

In this phase, the status of the call should already be ("בטיפול") because a first input was submitted by the agent, but it is still "פניה חדשה":


It seems that the automatic status change is triggered when a first task is being marked as completed, instead of when agent submits first input.

this problem was found while performing QA over https://github.com/hasadna/reportit-agent/issues/65 fix, as you can see there, the described expected behavior was already implemented.

It reproduces #