Use dedicated build jobs for every configuration

[godrose]

Should define specific .yaml files for each one of the 4 available configs:

• EndToEndWithFake - should build the client in DebugWithSpecs config and the e2e specs in EndToEndWithFake config

• IntegrationWithFake - should build the integration specs in IntegrationWithFake config

• EndToEndWithReal - should build the client in DebugWithSpecs config and the server in DebugWithSpecs config and the e2e specs in EndToEndWithReal config

• IntegrationWithReal - should build the integration specs in IntegrationWithReal config and the server in DebugWithSpecs config