Add tests.

[dblock]

Description

• Add tests for /_cluster/state.
• Added tests for /_count, /{index}/_count and added missing terminated_early.
• Moved _dangling tests into core.
• Added tests for /_data_stream/_stats.
• Added tests for /{index}/_delete_by_query.

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.

[github-actions]

Changes Analysis

Commit SHA: 5e10556
Comparing To SHA: 1316e77

API Changes

Summary

└─┬Paths
  ├─┬/{index}/_count
  │ ├─┬GET
  │ │ └─┬Responses
  │ │   └─┬200
  │ │     └─┬application/json
  │ │       └─┬Schema
  │ │         └──[➕] properties (25600:15)
  │ └─┬POST
  │   └─┬Responses
  │     └─┬200
  │       └─┬application/json
  │         └─┬Schema
  │           └──[➕] properties (25600:15)
  └─┬/_count
    ├─┬GET
    │ └─┬Responses
    │   └─┬200
    │     └─┬application/json
    │       └─┬Schema
    │         └──[➕] properties (25600:15)
    └─┬POST
      └─┬Responses
        └─┬200
          └─┬application/json
            └─┬Schema
              └──[➕] properties (25600:15)

Document Element	Total Changes	Breaking Changes
paths	4	0

• Total Changes: 4
• Additions: 4

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/10704863021/artifacts/1891864793

API Coverage

	Before	After	Δ
Covered (%)	533 (52.2 %)	533 (52.2 %)	0 (0 %)
Uncovered (%)	488 (47.8 %)	488 (47.8 %)	0 (0 %)
Unknown	26	26	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
559	267 (47.76 %)