Auto-close CT's outgoing channels when observing growing failed transactions of ticket redemption

[QYuQianchen]

Description

Nodes (running with hoprd <v.2.1.4) may have run into a growing number of rejected tickets on certain channels when the unrealized balance of that channel is close to their threshold. The bug has been fixed in the new hoprd release v2.1.4.

However, the complete mitigation requires nodes to close those problematic incoming payment channels, and some failed to perform channel closure. An alternative is to let the source of channel (i.e. CT nodes) close them as outgoing channels.

Moreover, CT nodes can introduce an automated job so that when the number of failed ticket redemption transactions gets continuously increased over time (e.g. The failed redemption txn count of the current channel epoch, over past 1000 blocks ,exceeds 5) for certain outgoing channels, CT should actively close them.

Definition of done

• Create data source to minitor the number of failed ticket redemption per channel between now-x blocks ago and now hopr-devrel#368
• Include that datasource into the criterial for auto-closing outgoing channels