Convert Key to ResourceName in v2 services (world-federation-of-advertisers/cross-media-measurement#111)
Convert Key to ResourceName in v2 services (world-federation-of-advertisers/cross-media-measurement#111)

* Convert Key to ResourceName in v2 services

* added ProtocolConfigKey for HeraldTest

* fix lint

* using failgrpc methods

* exception when neither DataProvider nor ModelProvider provided

* fix error message

* fix error message in test

* dropping v2 in variable name

* lint fix

* fix HeraldTest dependency

* making resource keys public for all repos

* make exchangestepattemptid equal to attempt number

* make exchangestepid equal to step index
world-federation-of-advertisers/common-jvm,world-federation-of-advertisers/common-jvm