add rake task to fix attestation data

[benedictfischer09]

Based on the issues reported in #6098 some of the attestation data was stored incorrectly in the database. This rake task is able to fix two issues 1) missing kindVersion field 2) double encoded verificationMaterial.certificate.rawBytes

Before

curl http://localhost:3000/api/v1/attestations/faraday-2.14.0 | jq | grep -A 3 kindVersion
no matches

cosign verify-blob --bundle faraday-2.14.0.sigstore.json --certificate-identity-regexp "https://github.com/lostisland/faraday/.github/workflows/publish.yml@refs/tags/v2.14.0" --certificate-oidc-issuer "https://token.actions.githubusercontent.com" faraday-2.14.0.gem
Error: bundle does not contain cert for verification, please provide public key
error during command execution: bundle does not contain cert for verification, please provide public key

After bundle exec rake attestations:repair

curl http://localhost:3000/api/v1/attestations/faraday-2.14.0 | jq | grep -A 3 kindVersion
"kindVersion": {
"kind": "dsse",
"version": "0.0.1"
},

cosign verify-blob --bundle faraday-2.14.0-fixed.sigstore.json --certificate-identity-regexp "https://github.com/lostisland/faraday/.github/workflows/publish.yml@refs/tags/v2.14.0" --certificate-oidc-issuer "https://token.actions.githubusercontent.com" faraday-2.14.0.gem
Verified OK

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.46%. Comparing base (164a40e) to head (46394d9).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6141      +/-   ##
==========================================
- Coverage   97.24%   94.46%   -2.78%     
==========================================
  Files         476      476              
  Lines        9785     9844      +59     
==========================================
- Hits         9515     9299     -216     
- Misses        270      545     +275     

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[jenshenny]

I think this is fine. I would prefer it to be a maintenance task eg. something like app/tasks/maintenance/user_totp_seed_empty_to_nil_task.rb with a dry run dropdown option. There's only ~4000 attestation records in the db + if this will be deleted after it's run then a rake task is ok.

I'd be curious to see the dry run results before any records are changed.