Corrected OpenSearch Version 2.6

[TackAdam]

Description

[Describe what this change achieves]
Correcting Version from 2.x to 2.6

Issues Resolved

[List any issues this PR will resolve]

Check List

• New functionality includes testing.
  • All tests pass, including unit test, integration test and doctest
• New functionality has been documented.
  • New functionality has javadoc added
  • New functionality has user manual doc added
• Commits are signed 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.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (2.6@c046499). Click here to learn what that means.
The diff coverage is n/a.

@@          Coverage Diff           @@
##             2.6     #561   +/-   ##
======================================
  Coverage       ?   38.04%           
======================================
  Files          ?      260           
  Lines          ?    15845           
  Branches       ?     4269           
======================================
  Hits           ?     6029           
  Misses         ?     9775           
  Partials       ?       41           

Flag	Coverage Δ
dashboards-observability	38.04% <0.00%> (?)

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