Add `push-configs` command

[jefflester]

Note: Completion of #113 is required before moving forward with this enhancement.

Add a push-configs command. This command will push ~/.minitrino/etc/ to cluster container(s) and then restart them (we could make a shared restart function for this part of the flow given the addition of minitrino restart #113).

Open questions:

• How do we manage pushing configs to clusters with workers? Maybe...
  • Push configs to the coordinator first
  • Run the copy logic utilized by the provision_workers function to copy the updated coordinator /etc/${CLUSTER_DIST}/ configs
  • Restart the coordinator and the workers
• How do we ensure we're adding a new file or a new version of an existing file? How do we handle replacing existing files?
  • Honestly, I think the equivalent of docker cp is okay. Any config file in ~/.minitrino/etc/ is subject to replacing target /etc/${CLUSTER_DIST}/${file} files whenever minitrino push-configs is executed.

Other notes:

• Ensure we account for this new directory when running snapshot commands. We won't be able to preserve the context of when the user ran minitrino push-configs, but we can at least ensure we add ~/.minitrino/etc/ to the snapshot tarball.

[jefflester]

@callard-starburst I'm putting this on hold for now, so if you work on anything, please postpone this one for now. Let's chat about it more this Friday. Thank you!

[jefflester]

@callard-starburst as discussed today, here's the pseudocode that should pretty much fo what we're after.

General logic:

-> minitrino push-config
-> exec_in_container(container_name, "echo 'ACTIVE' > /tmp/push-config-status.txt")
-> docker cp ~/.minitrino/etc/ ${container_name}:/tmp/etc/
-> docker restart ${container_name}
-> entrypoint: cp /tmp/etc/ /etc/${CLUSTER_DIST}
-> entrypoint: echo 'INACTIVE' > /tmp/push-config-status.txt
-> entrypoint: rm -rf /tmp/etc/*
-> entrypoint: start service

Handling workers:

-> Work through logic above for coordinator
-> Tear down existing workers
-> Run ctx.cluster.ops.provision_workers() where num_workers = previous_num_workers