Remove conditions for sending

[DyrellC]

Description of change

There is a race condition occurring between the tip requesting, and the broadcast and reply stages. There is a write flag being switched on and off by the various threads that stop the sendQueue from being polled from and sent to neighbours. As a result, we see a large spike in dropped transaction requests, and the node will stop synchronising. Once a node runs into this error the only remedy is to drop and reconnect the neighbour, and even then the problem could resurface any time there's a large amount of transactions being processed simultaneously.

To fix this we can remove the back and forth switching of this write flag.

Type of change

• Bug fix (a non-breaking change which fixes an issue)

How the change has been tested

Nodes no longer froze when synchronising with neighbours.

Change checklist

• My code follows the contribution guidelines for this project
• I have performed a self-review of my own code
• New and existing unit tests pass locally with my changes

[GalRogozinski]

Unit tests fail

[GalRogozinski]

closed in favor of #1864