Feature: expose CreatedAt and UpdatedAt from ruleset

[ivanmartos]

Currently Ruleset struct is not exposing fileds CreatedAt and UpdatedAt.
These fields are returned in respose JSON for api orgs/ORG_NAME/rulesets and orgs/ORG_NAME/rulesets/ORG_ID as fields

  "created_at": "2024-09-05T16:44:33.875+02:00",
  "updated_at": "2024-09-06T08:30:00.248+02:00",

Can these fields be please exported in

go-github/github/repos_rules.go

Line 536 in 06f85a4

type Ruleset struct {

?
Thanks