Update imports.

[Yury-Fridlyand]

Description

Some components were moved from common to core in opensearch-project/OpenSearch#5902. Then ml-commons were updated to reflect this in opensearch-project/ml-commons#741.
This PR includes:

• Update imports
• Reorder imports to keep them in alphabetical order
• Replace org.apache.lucene.util.SetOnce by org.opensearch.common.SetOnce as it was required to obsoleted API check

Issues Resolved

Fixes #125

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed as per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[navneet1v]

@Yury-Fridlyand

Thanks for opening this pull request.
We already have a pull request in progress which is fixing this same issue: #129

We are waiting on ml-commons repository to fix their repository zips so that checks can be successful.

[Yury-Fridlyand]

Oops. You can close my PR, I missed #129.
I fixed ml-commons today in opensearch-project/ml-commons#779. It uploads shadow jars (not zips) and ./gradlew run and ./gradlew build pass.
You can restart GHA to validate.

[navneet1v]

sure let me close this PR.