feat: Add ArchivedAt field to Organization struct

[MichaelSp]

Summary

The GitHub REST API has supported organization archiving since September 2023. The GET /orgs/{org} endpoint returns an archived_at timestamp field that is non-null when the org has been archived, but the Organization struct does not map this field.

This PR adds ArchivedAt *Timestamp to the Organization struct so callers can detect archived organizations without resorting to a raw HTTP request and a hand-rolled struct.

Changes

• github/orgs.go: add ArchivedAt *Timestamp \json:"archived_at,omitempty"`toOrganization`
• github/github-accessors.go: generated GetArchivedAt() accessor
• github/github-accessors_test.go: generated TestOrganization_GetArchivedAt test

All files generated via go generate ./github/....

References

• GitHub Changelog: https://github.blog/changelog/2023-09-06-organization-archiving-general-availability/
• API docs: https://docs.github.com/en/rest/orgs/orgs#get-an-organization

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.70%. Comparing base (0f881f5) to head (ca1dadf).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4179      +/-   ##
==========================================
+ Coverage   93.20%   93.70%   +0.50%     
==========================================
  Files         210      210              
  Lines       24622    19745    -4877     
==========================================
- Hits        22948    18502    -4446     
+ Misses       1478     1047     -431     
  Partials      196      196              

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[gmlewis]

Thank you, @MichaelSp!
LGTM.
Merging.