Get OPENSEARCH_VERSION from upstream package.json file

[cwperks]

Description

This PR undoes some of the changes from #2190 to get this version centrally from opensearch-dashboard's package.json file.

This PR resolves an issue seen on version increment PRs where the automation is not getting these hardcoded instances of the version.

Category

[Enhancement, New feature, Bug fix, Test fix, Refactoring, Maintenance, Documentation]

Maintenance

Check List

• New functionality includes testing
• New functionality has been documented
• 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

All modified and coverable lines are covered by tests ✅

Project coverage is 72.01%. Comparing base (391fe2f) to head (7fcfe42).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2246   +/-   ##
=======================================
  Coverage   72.01%   72.01%           
=======================================
  Files          98       98           
  Lines        2691     2691           
  Branches      420      412    -8     
=======================================
  Hits         1938     1938           
  Misses        638      638           
  Partials      115      115           

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