Revert "Merge branch 'andrey-sanity-readiness-api' into 'master'"

Purpose of revert

Revert "Merge branch 'andrey-sanity-readiness-api' into 'master'"

This reverts merge request !166444 (merged).

This caused all the tests in staging-ref and staging-cny to fail.

Failed pipelines

staging-cny: https://ops.gitlab.net/gitlab-org/quality/staging-canary/-/pipelines/3729230

staging-ref: https://ops.gitlab.net/gitlab-org/quality/staging-ref/-/pipelines/3729316

Checklist

• Create an issue to reinstate the merge request and assign it to the author of the reverted merge request.
• If the revert is to resolve a broken 'master' incident, please read through the Responsibilities of the Broken master resolution DRI.
• If the revert involves a database migration, please read through Deleting existing migrations.
• Add the appropriate labels before the MR is created. We can skip CI/CD jobs only if the labels are added before the CI/CD pipeline is created.

Milestone info

• I am reverting something in the current milestone. No changelog is needed, and I've added a ~"regression:*" label.
• I am reverting something in a different milestone. A changelog is needed, and I've removed the ~"regression:*" label.

Related issues and merge requests

Related issue: #494003 (closed)

Related MR: !166444 (merged)