Tests

Make max read size configurable #910

Job	Run time
unit	4m 27s
e2e (TestMultipleChainHorcrux)	5m 9s
e2e (TestChainPureHorcrux)	5m 2s
e2e (TestDownedSigners2of3)	7m 11s
e2e (TestDownedSigners3of5)	8m 31s
e2e (TestLeaderElection2of3)	5m 48s
e2e (Test2Of3SignerThreeSentries)	5m 9s
e2e (Test2Of3SignerThreeSentriesUniqueConnection)	4m 59s
e2e (TestUpgradeValidatorToHorcrux)	4m 59s
e2e (TestSingleSignerTwoSentries)	4m 50s
e2e (TestHorcruxProxyGRPC)	5m 23s
	1h 1m 28s

Provide feedback