[Schema Inaccuracy] `check-run` conclusion lacks `stale`, `security-and-analysis` lacks `secret_scanning_validity_checks`, installation-token example uses another repository shape

[HardMax71]

Schema Inaccuracy

A few response schemas in the 2022-11-28 description on main (c6721f3) don't match what the API returns or what their own examples show. They're small and separate, so I've put them together; happy to split them if that's easier to track.

1. The check-run schema's conclusion enum has success, failure, neutral, cancelled, skipped, timed_out and action_required, but not stale. The REST checks guide says "If a check run is in an incomplete state for more than 14 days, then the check run's conclusion becomes stale", and the POST /repos/{owner}/{repo}/check-runs body lists stale with the note "only GitHub can set this". check-suite.conclusion already includes stale.
2. security-and-analysis has no secret_scanning_validity_checks, though GET /repos/{owner}/{repo} returns it for admins next to the other secret scanning settings.
3. The installation-token example (#/components/examples/installation-token) gives its repositories network_count, subscribers_count and template_repository, which belong to full-repository. The response schema's repositories items are #/components/schemas/repository, which has none of the three. [Schema Inaccuracy] Example and schema mismatch for #/paths/~1app~1installations~1{installation_id}~1access_tokens/post #5662 reported template_repository and was closed after a check against 5b1274f, but that commit and main still have it in the example and not in the schema.

Expected

1. check-run.conclusion includes stale.
2. security-and-analysis has secret_scanning_validity_checks with the same {status: enabled|disabled} shape as its neighbours.
3. The example matches repository, or the schema says which repository shape the endpoint returns.

Reproduction Steps

$ jq -c '.components.schemas["check-run"].properties.conclusion.enum' api.github.com.2022-11-28.json
["success","failure","neutral","cancelled","skipped","timed_out","action_required"]

$ jq -c '.components.schemas["check-suite"].properties.conclusion.enum' api.github.com.2022-11-28.json
["success","failure","neutral","cancelled","skipped","timed_out","action_required","startup_failure","stale",null]

$ gh api -H "X-GitHub-Api-Version: 2022-11-28" repos/HardMax71/amiss --jq .security_and_analysis
{"dependabot_security_updates":{"status":"enabled"},"secret_scanning":{"status":"enabled"},"secret_scanning_non_provider_patterns":{"status":"disabled"},"secret_scanning_push_protection":{"status":"enabled"},"secret_scanning_validity_checks":{"status":"disabled"}}

$ jq -c '.components.schemas["security-and-analysis"].properties | keys' api.github.com.2022-11-28.json
["advanced_security","code_security","dependabot_security_updates","secret_scanning","secret_scanning_ai_detection","secret_scanning_delegated_alert_dismissal","secret_scanning_delegated_bypass","secret_scanning_delegated_bypass_options","secret_scanning_non_provider_patterns","secret_scanning_push_protection"]

$ jq -c '.components.examples["installation-token"].value.repositories[0] | [has("network_count"), has("subscribers_count"), has("template_repository")]' api.github.com.2022-11-28.json
[true,true,true]

$ jq -c '.components.schemas.repository.properties | [has("network_count"), has("subscribers_count"), has("template_repository")]' api.github.com.2022-11-28.json
[false,false,false]