Add ignore_unmapped support in KNNQueryBuilder

[ryanbogan]

Description

Add ignore_unmapped support in KNNQueryBuilder

Issues Resolved

#1018

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.

[codecov]

Codecov Report

Merging #1071 (c3211e8) into main (ca5e483) will decrease coverage by 0.06%.
The diff coverage is 75.86%.

@@             Coverage Diff              @@
##               main    #1071      +/-   ##
============================================
- Coverage     85.01%   84.96%   -0.06%     
- Complexity     1184     1192       +8     
============================================
  Files           159      159              
  Lines          4813     4842      +29     
  Branches        433      440       +7     
============================================
+ Hits           4092     4114      +22     
- Misses          525      530       +5     
- Partials        196      198       +2     

Files	Coverage Δ
.../main/java/org/opensearch/knn/index/IndexUtil.java	57.97% <75.00%> (+2.23%)	⬆️
...rg/opensearch/knn/index/query/KNNQueryBuilder.java	83.23% <76.19%> (-0.98%)	⬇️

[ryanbogan]

This isn't quite ready for review yet, I still need to add tests

[martin-gaievski]

This isn't quite ready for review yet, I still need to add tests

you can create PR as "draft" so CI will be triggered, and when you're done with coding just flip status to "Ready for review"

[ryanbogan]

This isn't quite ready for review yet, I still need to add tests

you can create PR as "draft" so CI will be triggered, and when you're done with coding just flip status to "Ready for review"

I had it as draft, then accidentally clicked on ready for review before I remembered about adding tests.

[ryanbogan]

Ready for review now

[navneet1v]

@ryanbogan before review start can you see why the github WFs are failings. and fix them

[ryanbogan]

@ryanbogan before review start can you see why the github WFs are failings. and fix them

@navneet1v The Linux failure is for the test org.opensearch.knn.index.KNNCircuitBreakerIT.testCbUntrips, and the same test/seed is passing on my local. Could it potentially be a flaky test?

For the others, I was informed during standup that the tests with the security plugin enabled are currently broken.

[navneet1v]

@ryanbogan before review start can you see why the github WFs are failings. and fix them

@navneet1v The Linux failure is for the test org.opensearch.knn.index.KNNCircuitBreakerIT.testCbUntrips, and the same test/seed is passing on my local. Could it potentially be a flaky test?

For the others, I was informed during standup that the tests with the security plugin enabled are currently broken.

Can we rerun the workflows. Secure cluster I know is broken. But lets fix the changelog step, by adding this change in CHANGELOG.md file

[martin-gaievski]

I have doubt about this change being backward compatible in its current form, please make sure BWC tests are passing

[navneet1v]

minor comment overall code looks good.

[martin-gaievski]

looks good to me