Added handling for unauth error

[eric-forte-elastic]

Pull Request

Issue link(s):
Resolves #5114

Summary - What I changed

Small update to handle unauthorized error in addition to the existing 404 errors. Example error: https://github.com/elastic/detection-rules/actions/runs/17740182447/job/50414401327.
Will now generate the following:

OR

In this case we need to use text as the 401 error can be either bad credentials or needs auth.

❯ curl --request GET \
            --url "https://api.github.com/gists/0443cfb5016bed103f1940b2f336e45a" \
            --header "accept: application/vnd.github.v3+json"
{
  "message": "Requires authentication",
  "documentation_url": "https://docs.github.com/rest",
  "status": "401"
}⏎                                                                                             
…r-gist-error-handling [$?] is  v1.4.2 via  v3.12.11 (detection-rules-build) on  eric.forte
❯ curl --request GET \
      --url "https://api.github.com/gists/0443cfb5016bed103f1940b2f336e45a" \
      --header "Authorization: token 123" \
      --header "accept: application/vnd.github.v3+json"
{
  "message": "Bad credentials",
  "documentation_url": "https://docs.github.com/rest",
  "status": "401"
}⏎

How To Test

Run python -m detection_rules dev update-navigator-gists with an invalid token.

Checklist

• Added a label for the type of pr: bug, enhancement, schema, maintenance, Rule: New, Rule: Deprecation, Rule: Tuning, Hunt: New, or Hunt: Tuning so guidelines can be generated
• Added the meta:rapid-merge label if planning to merge within 24 hours
• Secret and sensitive material has been managed correctly
• Automated testing was updated or added to match the most common scenarios
• Documentation and comments were added for features that require explanation

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• Have you signed the contributor license agreement?
• Have you followed the contributor guidelines?

[github-actions]

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