[Schema Inaccuracy] /zen defined content-type application/json instead of text/plain

Locate the OpenAPI schema definition for the /zen endpoint and compare its declared response content type with the reproduced GitHub response. Update the schema so the successful response uses text/plain, then run the repository's available schema validation checks; done means the /zen response is no longer declared as application/json.

Schema Inaccuracy

The correct content-type for /zen is text/plain. The schema has it defined as application/json.

❯ gh api --verbose /zen -H "Accept: application/json" | cat -
* Request at 2025-01-11 21:51:12.577489 -0800 PST m=+0.114637167
* Request to https://api.github.com/zen
> GET /zen HTTP/1.1
> Host: api.github.com
> Accept: application/json
> Authorization: token ████████████████████
> Content-Type: application/json; charset=utf-8
> Time-Zone: America/Los_Angeles
> User-Agent: GitHub CLI 2.64.0

< HTTP/2.0 200 OK
< Access-Control-Allow-Origin: *
< Access-Control-Expose-Headers: ETag, Link, Location, Retry-After, X-GitHub-OTP, X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Used, X-RateLimit-Resource, X-RateLimit-Reset, X-OAuth-Scopes, X-Accepted-OAuth-Scopes, X-Poll-Interval, X-GitHub-Media-Type, X-GitHub-SSO, X-GitHub-Request-Id, Deprecation, Sunset
< Content-Security-Policy: default-src 'none'
< Content-Type: text/plain;charset=utf-8
< Date: Sun, 12 Jan 2025 05:51:12 GMT
< Referrer-Policy: origin-when-cross-origin, strict-origin-when-cross-origin
< Server: github.com
< Strict-Transport-Security: max-age=31536000; includeSubdomains; preload
< Vary: Accept-Encoding, Accept, X-Requested-With
< X-Content-Type-Options: nosniff
< X-Frame-Options: deny
< X-Github-Api-Version-Selected: 2022-11-28
< X-Github-Request-Id: 61E4:215140:B3C230D:B7775AA:67835850
< X-Ratelimit-Limit: 5000
< X-Ratelimit-Remaining: 4988
< X-Ratelimit-Reset: 1736663997
< X-Ratelimit-Resource: core
< X-Ratelimit-Used: 12
< X-Xss-Protection: 0

Responsive is better than fast.
* Request took 360.29825ms

Expected

Expected content-type is text/plain

Reproduction Steps

gh api --verbose /zen -H "Accept: application/json" | cat -

I've checked for this in 3.10, 3.11, 3.12, 3.13, 3.14.