[Move @kbn/config-schema to server] kbn-io-ts-utils

[afharo]

Summary

Part of #189476.

We want to avoid @kbn/config-schema from leaking to the browser, and this package depends on it.

More specifically, this PR removes an unused API from the @kbn/io-ts-utils package to remove its dependency on @kbn/config-schema.

For maintainers

• This was checked for breaking API changes and was labeled appropriately

[elasticmachine]

Pinging @elastic/obs-knowledge-team (Team:obs-knowledge)

[kibana-ci]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: aace27c

Failed CI Steps

• Jest Integration Tests #4

Metrics [docs]

✅ unchanged

History

• 💔 Build #230645 failed 13bbe1b

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@elasticmachine merge upstream