Summary

Fixes #3340 and #3214

The GitHub API returns required_reviewers.reviewer.id as a JSON string (e.g., "12345"), but go-github's RulesetReviewer.ID field is *int64. Standard Go JSON unmarshaling rejects this with:

json: cannot unmarshal string into Go struct field RepositoryRuleset.rules.required_reviewers.reviewer.id of type int64

The POST/PUT succeeds (the ruleset is created/updated on GitHub), but the provider cannot parse the response — so the resource is never recorded in Terraform state, creating orphaned rulesets on every retry.

Why existing tests didn't catch this

The acceptance test TestAccGithubRepositoryRuleset_requiredReviewers (added in #3073) only runs when a maintainer adds the acctest label, and the CI matrix (anonymous, individual, organization) requires an org-mode run to pass the skipUnlessHasOrgs precheck. The unit tests for expandRequiredReviewers / flattenRequiredReviewers only exercise in-memory Go struct round-trips — they never parse raw JSON from the API, so they never hit the string→int64 mismatch that lives inside go-github's json.Unmarshal path.

Approach

Rather than patching go-github upstream, this adds thin wrapper functions around the ruleset CRUD API calls in util_rules.go. The wrappers use client.BareDo() to obtain the raw HTTP response body, apply a targeted regex ("id"\s*:\s*"(\d+)" → "id":$1) to convert quoted integer IDs to unquoted integers, then unmarshal into the standard go-github types.

This approach:

• Fixes both repository-level and organization-level rulesets
• Is safe because the only "id" field returned as a quoted integer in ruleset responses is reviewer.id (the top-level ruleset ID and other numeric fields are already returned as JSON numbers)
• Matches the URL construction and method signatures of the upstream go-github methods exactly
• Does not affect any other API calls

Changes

• github/util_rules.go: Added fixReviewerStringIDs() regex helper, doRulesetRequest() for raw response handling, and 6 wrapper functions (createRepoRuleset, getRepoRuleset, updateRepoRuleset, createOrgRuleset, getOrgRuleset, updateOrgRuleset)
• github/resource_github_repository_ruleset.go: Replaced 4 direct go-github calls with wrapper functions
• github/resource_github_organization_ruleset.go: Replaced 4 direct go-github calls with wrapper functions
• github/util_rules_test.go: Added unit tests for fixReviewerStringIDs (7 cases) and an end-to-end unmarshal round-trip test that simulates the actual buggy API response

Test plan

• Unit tests for fixReviewerStringIDs covering: quoted integer conversion, unquoted passthrough, no-space formatting, multiple IDs, non-digit strings, empty strings, full nested response
• End-to-end unmarshal test simulating the actual GitHub API response with string reviewer IDs — verifies the fix at the JSON layer where the bug actually occurs
• Existing TestExpandRequiredReviewers, TestFlattenRequiredReviewers, TestRoundTripRequiredReviewers still pass
• go vet ./... clean
• Full build succeeds
• Acceptance test TestAccGithubRepositoryRuleset_requiredReviewers — requires acctest label + org-mode CI run to exercise the real API round-trip