Do not require ShardFailure.primary field in shard failure error response

[janhoy]

Description

This change makes the primary field of ShardFailure spec optional in response from opensearch. Once a new spec is published, the new unit test in opensearch-project/opensearch-java#1878 will stop failing.

Issues Resolved

Fixes opensearch-project/opensearch-java#1877

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[github-actions]

Changes Analysis

Commit SHA: c44dc39
Comparing To SHA: 2954600

API Changes

Summary

└─┬Components
  └─┬Schemas
    └─┬_common___ShardFailure
      └──[➖] required (40840:11)❌ 

Document Element	Total Changes	Breaking Changes
components	1	1

• ❌ BREAKING Changes: 1 out of 1
• Removals: 1
• Breaking Removals: 1

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/22077743754/artifacts/5531060714

API Coverage

	Before	After	Δ
Covered (%)	666 (65.23 %)	666 (65.23 %)	0 (0 %)
Uncovered (%)	355 (34.77 %)	355 (34.77 %)	0 (0 %)
Unknown	145	145	0

[reta]

Thank you @janhoy

[karenyrx]

I don't think this is the correct fix, opened up #1040
cc @reta

[reta]

I don't think this is the correct fix, opened up #1040 cc @reta

Thank you @karenyrx , I think you are very right

[janhoy]

Closing in favor of other PR