Fix Activity trigger when triggered for all contacts
Two separate fix in this MR for Activity post trigger. When "For all contacts" is selected as "Triggered for":
- On the Edit trigger parameters form "Activity targets" is selected though "For all contacts" is written to DB and the trigger acts like that.
- The trigger gets triggered for the same contact twice even if the source and target/assignee is different.
After this fix the above works as expected.