Migrating .github/workflows off public github runners for rate limiting

[api-clients-generation-pipeline[bot]]

See DataDog/datadog-api-spec#3780 Test branch datadog-api-spec/test/campaigner/github/workflow/runner-update

[datadog-datadog-prod-us1[bot]]

Datadog Report

Branch report: datadog-api-spec/generated/3780 Commit report: 3cb5bcc Test service: datadog-api-client-ruby

:white_check_mark: 0 Failed, 18 Passed, 2108 Skipped, 50.11s Total duration (1m 6.76s time saved)

[github-actions[bot]]

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