Add missing failure fields in opensearchapi structs

[Jakob3xD]

Description

Add missing failure fields in opensearchapi structs displayed by errors:
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:79
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:206
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:211
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:425
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:564
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:647
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:877
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:890
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:911
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:918
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:925
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:940
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:949
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:957
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:965
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:980
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:1197
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:1215
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:1237
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:1255
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:1466
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:1486
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:1497
https://github.com/opensearch-project/opensearch-go/actions/runs/8560050080/job/23458155375#step:7:1510

Issues Resolved

List any issues this PR will resolve, e.g. Closes [...].

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.24%. Comparing base (06a6dc8) to head (a1b6fd0).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #510      +/-   ##
==========================================
+ Coverage   57.29%   63.24%   +5.94%     
==========================================
  Files         315      315              
  Lines        9823     7715    -2108     
==========================================
- Hits         5628     4879     -749     
+ Misses       2902     1550    -1352     
+ Partials     1293     1286       -7     

Flag	Coverage Δ
integration	55.78% <ø> (+4.94%)	⬆️
unit	81.45% <ø> (+68.60%)	⬆️

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

Files	Coverage Δ
opensearchapi/api_bulk.go	100.00% <ø> (ø)
opensearchapi/api_cat-nodeattrs.go	100.00% <ø> (ø)
opensearchapi/api_cat-nodes.go	100.00% <ø> (ø)
opensearchapi/api_cluster-stats.go	100.00% <ø> (ø)
opensearchapi/api_datastream-stats.go	100.00% <ø> (ø)
...archapi/api_document-delete_by_query_rethrottle.go	100.00% <ø> (ø)
opensearchapi/api_indices-block.go	100.00% <ø> (ø)
opensearchapi/api_indices-cache.go	100.00% <ø> (ø)
opensearchapi/api_indices-close.go	100.00% <ø> (ø)
opensearchapi/api_indices-flush.go	100.00% <ø> (ø)
... and 14 more

... and 229 files with indirect coverage changes

[Jakob3xD]

I am not sure how I can setup a broken Opensearch to test this in a practical way.

[dblock]

Note to us. This stuff should really be generated from spec.