[kathap]

• A short explanation of the proposed change:
  Make staging.auth optional in all four ccng config schemas (api, worker, clock, deployment_updater).

• An explanation of the use cases your change solves
  staging.auth (backed by BOSH properties cc.staging_upload_user/password) is only used by the local blobstore (local/local-temp-storage blobstore types, where local? = true). The local blobstore is only meaningful for local development — in a real BOSH deployment there is always more than one CC instance, so a local blobstore cannot be shared. All supported BOSH deployments use storage-cli (e.g. DAV, Azure, S3), where local? = false and staging.auth is never consulted. Making the field optional allows BOSH deployments to omit staging.auth from the config (once capi-release stops rendering it) without failing schema validation, while local dev setups that still supply it continue to work unchanged.

• Links to any other associated PRs
  Remove staging_upload_user and password capi-release#710

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• I have made this pull request to the main branch

• I have run all the unit tests using bundle exec rake

• I have run CF Acceptance Tests