Add version 1.3.9

[andrross]

BWC tests are failing on 2.x due to the release of 1.3.8.

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff
• Commit changes are listed out in CHANGELOG.md file (See: Changelog)

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[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: SUCCESS ✅
• URL: https://build.ci.opensearch.org/job/gradle-check/10602/
• CommitID: 04d9196

[reta]

Thanks @andrross , I think this step was automated, or not anymore?

[andrross]

Thanks @andrross , I think this step was automated, or not anymore?

@reta The version increment on the 1.3 branch is automated (#6163), but the change for BWC on the 2.x branch seems not to be automated (#4709 #5564).

[andrross]

@reta It is automated for the BWC version on the .x branch of the same major version (#6164) but seems to not look ahead to the next major version.

[reta]

@reta It is automated for the BWC version on the .x branch of the same major version (#6164) but seems to not look ahead to the next major version.

Oh I see, thanks @andrross

[andrross]

Actually, it is automated for the main branch when a 2.x version is added. Seems there's just this one case of patch release for the previous major version that isn't automated.

[reta]

@andrross do we need to bring this to 2.5 and main as well?

[andrross]

2.5 yes (#6176). main no because it doesn't have any support for the 1.x versions.