Add OpenAPI spec for RUM Teams Ownership public API - #4838

• All required reviewers must approve this pull request before it can be merged. Learn more in our FAQ.

• Needs approval from Team: web-frameworks-approvers

• Needs approval from Team: web-frameworks

  _{Questions about this check? Reach out in #dx-source-code-management on Slack.
  Digest: 39f264e}

• All applicable commits are signed and verified
  _{Digest: 8bffdd7}

• All applicable files are owned properly
  _{Digest: b5d5f93}

if this seems incorrect, you can retrigger the evaluation of the MergeGate by clicking on this link