Fixed /_search/scroll/{scroll_id}, missing search tests.

[dblock]

Description

• The /_search/scroll/{scroll_id} deprecated variant does not require scroll_id in the body because it's already in the path.
• Tests for GET and POST /_search.
• Tests for GET /_search/pipeline and DELETE /_search/pipeline/{id}.
• Tests for remainder of _search/point_in_time.

Issues Resolved

Part of #663.

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[github-actions]

Changes Analysis

Commit SHA: b3745d4
Comparing To SHA: b2c8c46

API Changes

Summary

└─┬Paths
  ├─┬/_search/scroll/{scroll_id}
  │ ├─┬GET
  │ │ └─┬Requestbody
  │ │   └─┬application/json
  │ │     └─┬Schema
  │ │       ├──[➖] required (27470:17)❌ 
  │ │       └──[➖] description (27471:26)
  │ └─┬POST
  │   └─┬Requestbody
  │     └─┬application/json
  │       └─┬Schema
  │         ├──[➖] required (27470:17)❌ 
  │         └──[➖] description (27471:26)
  └─┬/_search/scroll
    ├─┬GET
    │ └─┬Requestbody
    │   └─┬application/json
    │     └─┬Schema
    │       ├──[➖] required (27470:17)❌ 
    │       └──[➖] description (27471:26)
    └─┬POST
      └─┬Requestbody
        └─┬application/json
          └─┬Schema
            ├──[➖] required (27470:17)❌ 
            └──[➖] description (27471:26)

Document Element	Total Changes	Breaking Changes
paths	8	4

• ❌ BREAKING Changes: 4 out of 8
• Removals: 8
• Breaking Removals: 4

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/12361446786/artifacts/2328624342

API Coverage

	Before	After	Δ
Covered (%)	606 (59.35 %)	606 (59.35 %)	0 (0 %)
Uncovered (%)	415 (40.65 %)	415 (40.65 %)	0 (0 %)
Unknown	43	43	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
536	506 (94.4 %)

[Tokesh]

Looking perfect as usual. It looks like the OS version might need to be updated in one of the tests.

[Tokesh]

Thank you, LGTM! Great job