* Separate out file_mounts contents hashing into its own separate hash
Add an option to continuously sync file_mounts from head node to worker nodes:
monitor.py will re-sync file mounts whenver contents change but will only run setup_commands if the config also changes
* add test and default value for file_mounts_sync_continuously
* format code
* Update comments
* Add param to skip setup commands when only file_mounts content changed during monitor.py's update tick
Fixed so setup commands run when ray up is run and file_mounts content changes
* Refactor so that runtime_hash retains previous behavior
runtime_hash is almost identical as before this PR. It is used to determine if setup_commands need to run
file_mounts_contents_hash is an additional hash of the file_mounts content that is used to detect when only file syncing has to occur.
Note: runtime_hash value will have changed from before the PR because we hash the hash of the contents of the file_mounts as a performance optimization
* fix issue with hashing a hash
* fix bug where trying to set contents hash when it wasn't generated
* Fix lint error
Fix bug in command_runner where check_output was no longer returning the output of the command
* clear out provider between tests to get rid of flakyness
* reduce chance of race condition from node_launcher launching a node in the middle of an autoscaler.update call
Ian Rodney