[WIP] Automate Comparison of Checksums for Forest and Lotus Snapshots

[jdjaustin]

Summary of changes

Changes introduced in this pull request:

• We are already running both Forest and Lotus with the benchmark script, so this PR will extend that script to export a snapshot during the Forest client run and compare the checksum against the downloaded Lotus snapshot's checksum.

Reference issue to close (if applicable)

Closes #2559

Other information and links

Change checklist

• I have performed a self-review of my own code,
• I have made corresponding changes to the documentation,
• I have added tests that prove my fix is effective or that my feature works (if possible),
• I have made sure the CHANGELOG is up-to-date. All user-facing changes should be reflected in this document.

[jdjaustin]

@elmattic I haven't been able to get the snapshot export logic to work for Lotus. If you have some time to help troubleshoot, that might be helpful. But no need to spend much time on it; I think I'm just going to work on restoring the --tipset functionality to Forest so we can use that approach.

[jdjaustin]

Blocked by #2999

[jdjaustin]

Plan to open a new issue in forest-iac after benchmark script is moved and after PR to restore --tipset flag has landed.