message: Make backstage-service code owner for yarn.lock files
diff: # https://help.github.com/articles/about-codeowners/
  * @backstage/reviewers
  +yarn.lock @backstage/reviewers @backstage-service
  +*/yarn.lock @backstage/reviewers @backstage-service
  /.changeset/cost-insights-* @backstage/reviewers @backstage/silver-lining
  /.changeset/search-* @backstage/reviewers @backstage/techdocs-core
  /.changeset/techdocs-* @backstage/reviewers @backstage/techdocs-core
  