Complete variations of /{index}/alias/{name} tests, add tests for HEAD, bulk, analyzers.

[dblock]

Description

• Added tests for HEAD /.
• Complete alias tests in the correct files, added indices.exists_alias@404.
• Added more helpful info on using coverage reports.
• Added tests for PUT /_bulk and /{index}/_bulk.

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[github-actions]

Changes Analysis

Commit SHA: ab1bedf
Comparing To SHA: ceefc37

API Changes

Summary

├─┬Paths
│ ├─┬/{index}/_alias/{name}
│ │ ├─┬GET
│ │ │ └─┬Responses
│ │ │   └──[➕] codes (25761:7)
│ │ └─┬HEAD
│ │   └─┬Responses
│ │     └──[➕] codes (25721:7)
│ ├─┬/{index}/_alias
│ │ └─┬GET
│ │   └─┬Responses
│ │     └──[➕] codes (25761:7)
│ ├─┬/_alias/{name}
│ │ ├─┬GET
│ │ │ └─┬Responses
│ │ │   └──[➕] codes (25761:7)
│ │ └─┬HEAD
│ │   └─┬Responses
│ │     └──[➕] codes (25721:7)
│ └─┬/_alias
│   └─┬GET
│     └─┬Responses
│       └──[➕] codes (25761:7)
└─┬Components
  ├──[➕] responses (25761:7)
  └──[➕] responses (25721:7)

Document Element	Total Changes	Breaking Changes
paths	6	0
components	2	0

• Total Changes: 8
• Additions: 8

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/10491086295/artifacts/1837544646

API Coverage

	Before	After	Δ
Covered (%)	524 (51.32 %)	524 (51.32 %)	0 (0 %)
Uncovered (%)	497 (48.68 %)	497 (48.68 %)	0 (0 %)
Unknown	26	26	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
550	351 (63.82 %)

[nhtruong]

since the schema for application/json is not defined, does that mean we don't care what it is, or it's an empty JSON, or a null for body?

[dblock]

There's actually a schema, but I am deferring this to #445 if that's ok.