Add samples to exceptions

[hepcat72]

Summary Change Description

I intend to gather the list of all samples to add to the animal/sample table from the AllMissingSamples exception class. That class however did not have individual sample names from files where all samples were missing. Those were reported in separate NoSamplesError exceptions (for brevity). This PR adds the sample names to the exception object (but still keeps the error succinct.

I also split the NoSamplesError into 2 exceptions: NoSamplesError and NoSampleHeaders, which were 2 cases that it was originally raised for.

Affected Issues/Pull Requests

• Partially addresses #829
• Merges into PR #926
• Next PR: #929

Review Notes

Note that initially, I accidentally committed and pushed the changes to the branch in the upstream PR (926). I did a git reset, branched-committed-pushed, switched back to the reverted parent branch, and force-pushed it. I hope that doesn't cause any issue.

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)