[bisq-network/bisq] Involuntary reject mediator suggestion (#4022)

[MwithM]

<!--
   SUPPORT REQUESTS: This is for reporting bugs in the Bisq app.
   If you have a support request, please join #support on Bisq's
   Keybase team at https://keybase.io/team/Bisq
-->

### Description

Feature proposal to stop accidental confirmation of payment receipt after agreeing with mediator's suggestion.

#### Version

v1.2.7

### Steps to reproduce

Start a trade and take it to step 3 (Confirm payment receipt). Open support ticket and generate mediator suggestion. Accept mediator's proposal. 
If user clicks "confirm payment received" before the other peer accepts proposal, it doesn't matter that he already accepted mediator's proposal and the trade will continue like mediation did not happen.

### Expected behaviour

Create the option to stop trading process when support ticket is open.

### Screenshots
![mediation not accepted](https://user-images.githubusercontent.com/50149324/75710513-ff9c4c00-5cc4-11ea-85e0-dc4f22c9f829.jpg)

### Additional info

In some cases, delay acceptance of mediator's suggestion is a way to harm the other peer because there's very little incentives to quickly accept it and big asymmetry of payouts. This issue could affect new users, and also long time uncautious users, because trades can be in this state for a long time.

Issue somehow related to #3737, UX for mediation can improve.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/bisq-network/bisq/issues/4022
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bisq.network/pipermail/bisq-github/attachments/20200302/b0a53274/attachment-0001.html>