Remove the callback when a downloaded block headers is not found (#2582)
Remove the callback when a downloaded block headers is not found (#2582)

* Remove the callback when a downloaded block headers is not found

* act on review

Aprogiena/StratisBitcoinFullNode,stratisproject/StratisBitcoinFullNode,mikedennis/StratisBitcoinFullNode,mikedennis/StratisBitcoinFullNode,fassadlr/StratisBitcoinFullNode,Neurosploit/StratisBitcoinFullNode,Neurosploit/StratisBitcoinFullNode,bokobza/StratisBitcoinFullNode,quantumagi/StratisBitcoinFullNode,Aprogiena/StratisBitcoinFullNode,mikedennis/StratisBitcoinFullNode,stratisproject/StratisBitcoinFullNode,Neurosploit/StratisBitcoinFullNode,bokobza/StratisBitcoinFullNode,quantumagi/StratisBitcoinFullNode,bokobza/StratisBitcoinFullNode,bokobza/StratisBitcoinFullNode,Aprogiena/StratisBitcoinFullNode,fassadlr/StratisBitcoinFullNode,mikedennis/StratisBitcoinFullNode