Add support for multiple test verbs and fix /_render/template.

[dblock]

Description

You can now do this:

- synopsis: Use POST and PUT interchangeably.
  path: /{index}
  method:
    - POST
    - PUT

Avoids duplicating the test.

Added tests and fixed /_render/template.

Issues Resolved

Part of #663.

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[github-actions]

Changes Analysis

Commit SHA: 958c971
Comparing To SHA: c0237fb

API Changes

Summary

└─┬Paths
  ├─┬/_render/template/{id}
  │ ├─┬GET
  │ │ └─┬Requestbody
  │ │   └─┬application/json
  │ │     └─┬Schema
  │ │       ├──[➕] properties (27313:15)
  │ │       ├──[➖] properties (27313:15)❌ 
  │ │       └─┬params
  │ │         └──[🔀] additionalProperties (27321:39)❌ 
  │ └─┬POST
  │   └─┬Requestbody
  │     └─┬application/json
  │       └─┬Schema
  │         ├──[➕] properties (27313:15)
  │         ├──[➖] properties (27313:15)❌ 
  │         └─┬params
  │           └──[🔀] additionalProperties (27321:39)❌ 
  └─┬/_render/template
    ├─┬GET
    │ └─┬Requestbody
    │   └─┬application/json
    │     └─┬Schema
    │       ├──[➕] properties (27313:15)
    │       ├──[➖] properties (27313:15)❌ 
    │       └─┬params
    │         └──[🔀] additionalProperties (27321:39)❌ 
    └─┬POST
      └─┬Requestbody
        └─┬application/json
          └─┬Schema
            ├──[➕] properties (27313:15)
            ├──[➖] properties (27313:15)❌ 
            └─┬params
              └──[🔀] additionalProperties (27321:39)❌ 

Document Element	Total Changes	Breaking Changes
paths	12	8

• ❌ BREAKING Changes: 8 out of 12
• Modifications: 4
• Removals: 4
• Additions: 4
• Breaking Removals: 4
• Breaking Modifications: 4

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/12262734519/artifacts/2301701082

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	463 (86.38 %)

[nhtruong]

This is a great shorthand for writing the same chapter multiple times with different methods. I think we should treat it as such: Multiple chapters that virtually identical but the method. And then when the story is read, we will turn that 1 chapter of Create index "books" into two chapter:

• Create Index "book" [With POST]
• Create Index "book" [With PUT]

Then you will only have to modify the story parser to turn that 1 chapter into 2 and the rest of the framework can stay intact. We can add a line in this guide saying that the chapter will be split into 2 so they know what to expect in the Result page.

Arguably, a case like this should be treat as 2 different stories because rarely are our non-PUT requests idempotent (even when you delete a resource on OS twice, you get 404 the second time). So you could not actually test this on PUT/POST /books because executing PUT /books after POST /books will result in index named books already exists error. This will open a can of worm of matrix argument when we have multiple of such chapters in an original story.

[dblock]

Okay let me see if I can do a parser-based implementation instead ...

[dblock]

Closing in favor of #724