Add a connectToAllJobs option to MantisClient getSinkClient

[tcai-stripe]

Context

Currently JobSource attempts to fetch the scheduling information for the latest target job. This can be painful if a new job is spun up but has not fully Launched. Most of the time we're looking to communicate with latest and only latest but there are cases where ALL would be more useful.

exposes an option to configure whether the MantisClient get the latest SinkClient or all SinkClients.

Checklist

• [x] ./gradlew build compiles code correctly
• [ ] Added new tests where applicable
• [x] ./gradlew test passes all tests
• [ ] Extended README or added javadocs where applicable

[tcai-stripe]

cc @crioux-stripe

[crioux-stripe]

I think we may want to close this in favor of https://github.com/Netflix/mantis/pull/717 which achieves what we want but in a slightly different fashion.