fix(rome_cli): normalize the content of CLI snapshots

[leops]

Summary

This PR is an attempt at improving the general stability of CLI snapshot tests by "redacting" some unstable elements from the snapshot content that would be susceptible to change from one run to another. This includes the path to the current executable and the temporary directory, the time it takes for the CLI to execute, and the platform-specific path separator.

Test Plan

This should solve some of the stability issues we currently have with the CI runs, but not all of them though: we still have semi-random failures on the max_diagnostics tests that can be reproduced more easily on some platforms than other.