fix bug 3860 for no class issue

[jngz-es]

Description

Related Issues

#3860

Check List

• New functionality includes testing.
• New functionality has been documented.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

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

Attention: Patch coverage is 94.44444% with 1 line in your changes missing coverage. Please review.

Project coverage is 77.98%. Comparing base (ade09e6) to head (325c800).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...java/org/opensearch/ml/common/utils/Validator.java	94.44%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #3861      +/-   ##
============================================
- Coverage     78.02%   77.98%   -0.04%     
- Complexity     7338     7389      +51     
============================================
  Files           656      659       +3     
  Lines         33074    33278     +204     
  Branches       3708     3748      +40     
============================================
+ Hits          25806    25952     +146     
- Misses         5681     5720      +39     
- Partials       1587     1606      +19     

Flag	Coverage Δ
ml-commons	77.98% <94.44%> (-0.04%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.