Fix race condition between Sync and Apply actions

[spyglass-software]

We need to address the various ways that sync and apply commands can collide.

Scenario: Sync Occurs Before Apply Completion

1. Git push lands with an update such as roleGrants.finance_viewer.select.view = ["acme.prod.payments"]
2. The Apply action runs and prepares to execute grant select on view acme.prod.payments to role finance_viewer;
3. The Sync action runs, and, not seeing any role grants for finance_viewer, it deletes the recent line from the yaml and commits.
4. The Apply action continues and executes the grants in Snowflake.

Result: finance_viewer has grants in Snowflake but not in YAML. This will be resolved at the next Sync, but causes an unexpected user experience.