Don't wait forever in cc-worker

[sethboyles]

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Issue

cc-worker can block bosh from cancelling a deployment, since the post start waits forever:

https://github.com/cloudfoundry/capi-release/blob/5f061c8330efecfd61588cc3186248c5c2a3aff0/jobs/cloud_controller_worker/templates/post-start.sh.erb#L16

Steps to Reproduce

not sure

Expected result

the deployment fails, the task is cancelled, and the lock is deleted

Current result

the deployment fails, the task hangs when cancelled, and the lock is not deleted

Possible Fix

introduce some kind of timeout in the post-start script

name of issue screenshot

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