Payments never get SETTLED when spawning multiple activities

[nieznanysprawiciel]

Use reproduction scenario from task: #113

Although we have 2 payment confirmations, payments status is not set 2 SETTLED. Since second confirmation is agreement payment I assumed that it should be the last payment.

It still possible that I didn't wait enough time. Requires investigation.

Investigation:
Bugs seems strictly related to scenario, when we have multiple Activities. It seems that payments module doesn't work correctly in this case and never sets status to SETTLED. Problem is caused by this part of code:
https://github.com/golemfactory/yagna/blob/60d103cfcd9194a38afd285dc20f0651a3d9e22d/core/payment/src/dao/agreement.rs#L128-L131
We don't check activity payments here, so later this if https://github.com/golemfactory/yagna/blob/60d103cfcd9194a38afd285dc20f0651a3d9e22d/core/payment/src/dao/agreement.rs#L149-L157
isn't triggered.

The same happens for mid-agreement payments without multiple activities

[nieznanysprawiciel]

Other bug related to multi-activity scenario: #113