ci: configure renovate to ignore `@microsoft/api-extractor` (#42797)
ci: configure renovate to ignore `@microsoft/api-extractor` (#42797)

This is an interm solution until https://github.com/microsoft/rushstack/issues/2797 is fixed.

Related failures in the Angular repo https://app.circleci.com/jobs/github/angular/angular/1018749?utm_campaign=vcs-integration-link&utm_medium=referral&utm_source=github-build-link

PR Close #42797

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