CI poller needs release-bot token for private repo CI status checks

The getsentry/publish CI poller's cross-repo API calls (commit status, check suites, git refs) require the sentry-release-bot app token with owner: getsentry scope — not the sentry-internal-app token. The internal app isn't installed on all getsentry repos (e.g. sentry-xbox, sentry-playstation, sentry-switch, service-registry), causing 404s on all CI status API calls. Combined with the gh api --jq stdout error leak, this silently leaves issues stuck in ci-pending indefinitely. Fix (PR #7843): added a separate release-bot-token step and a gh_api_release helper that uses GH_TOKEN="$RELEASE_TOKEN" for all cross-repo calls.