Samples and Animals Loader fixes

[hepcat72]

Summary Change Description

Added loading of the FCirc model to the SamplesLoader. This was overlooked in the first go-round.

I removed the call to add_skip_row_index in the animal loader's get or create protocol method because the samples loader wasn't getting the required animal records and there should have been no issue. The treatment field is optional and it was just a warning.

Affected Issues/Pull Requests

• Partially addresses #829
• Merges into #1010
• Next PR: #1012

Review Notes

See comments in-line.

Checklist

This pull request will be merged once the following requirements are met. The author and/or reviewers should uncheck any unmet requirements:

• Review requirements
  • Minimum approvals: 1
  • No changes requested
  • All blocking issues resolved by reviewers
  • Specific reviewers: @add_username_here
  • Review period: 2 days
• Associated issue/pull request requirements:
  • [x] All requirements in affected issues marked "resolved" are satisfied
  • [x] All required pull requests are merged (or none)
• Basic requirements
  • [x] All linters pass
  • [x] All tests pass
  • [x] All conflicts resolved
• Overhead requirements
  • [x] New/changed method tests implemented/updated (or no change)
  • [ ] Updated Unreleased section of changelog.md (or no change)
  • [x] Migrations created & committed (or no change)

[hepcat72]

For the life of me, I cannot fix the linting error. The code is there. It's as if the linters are seeing different code. I suggest we just review this, then review the next one and merge it into this one to fix the issue. Then we can merge this. So nonsensical.