[Feature]: Incorrect fee estimation causes sBTC to be locked up indefinitely

[technovision99]

(High) Incorrect fee estimation causes sBTC to be locked up indefinitely

1. Description

The fix in #498 does indeed correctly lock up the max-fee from the user however our concern is that the code does not currently have a way to call reject-withdrawal-request as per #478 and #568. As a result if fee estimation fails for whatever reason (including a fee of 0) a user's sBTC will be locked indefinitely.

This issue should be resolved once calls to reject-withdrawal-request is implemented and called if the request's max-fee is not enough to pay for submitting the transaction fee on bitcoin.

[djordon]

Good call out. I think this is the same issue highlighted in #620, and I think the fix will be us doing one of the proposals listed there.