feat(config/secrets): add korkSecrets dependency to halyard-config

[KathrynLewis]

Part of secrets management project.

Depends on adding kork to spinnaker-dependencies here: https://github.com/spinnaker/spinnaker-dependencies/pull/279/files

spinnaker/spinnaker#3649

[spinnakerbot]

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• 9bed2d9: feat(config/secrets): add new annotations for secrets in configs

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