Add ml.delete_task and tweak ml schemas

[Xtansia]

Description

Add ml.delete_task and tweak ml schemas

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[github-actions]

Changes Analysis

Commit SHA: 7d36187
Comparing To SHA: 6f9c1c1

API Changes

Summary

├─┬Paths
│ ├─┬/{index}/_doc/{id}
│ │ ├─┬GET
│ │ │ └──Parameters
│ │ ├─┬PUT
│ │ │ ├──Parameters
│ │ │ └──Parameters
│ │ ├─┬POST
│ │ │ ├──Parameters
│ │ │ └──Parameters
│ │ ├─┬DELETE
│ │ │ ├──Parameters
│ │ │ └──Parameters
│ │ └─┬HEAD
│ │   └──Parameters
│ ├─┬/_plugins/_ml/tasks/{task_id}
│ │ └──[➕] delete (3966:7)
│ ├─┬/{index}/_source/{id}
│ │ ├─┬GET
│ │ │ └──Parameters
│ │ └─┬HEAD
│ │   └──Parameters
│ ├─┬/_opendistro/_rollup/jobs/{rollupID}
│ │ └─┬PUT
│ │   └──Parameters
│ ├─┬/_plugins/_rollup/jobs/{id}
│ │ └─┬PUT
│ │   └──Parameters
│ ├─┬/{index}/_termvectors/{id}
│ │ ├─┬GET
│ │ │ └──Parameters
│ │ └─┬POST
│ │   └──Parameters
│ ├─┬/{index}/_update/{id}
│ │ └─┬POST
│ │   └──Parameters
│ ├─┬/_cluster/state/{metric}
│ │ └─┬GET
│ │   └──Parameters
│ ├─┬/_cluster/state
│ │ └─┬GET
│ │   └──Parameters
│ ├─┬/_cluster/state/{metric}/{index}
│ │ └─┬GET
│ │   └──Parameters
│ ├─┬/{index}/_mtermvectors
│ │ ├─┬GET
│ │ │ └──Parameters
│ │ └─┬POST
│ │   └──Parameters
│ ├─┬/{index}/_doc
│ │ └─┬POST
│ │   ├──Parameters
│ │   └──Parameters
│ ├─┬/_plugins/_transform/{id}
│ │ └─┬PUT
│ │   └──Parameters
│ ├─┬/{index}/_create/{id}
│ │ ├─┬PUT
│ │ │ └──Parameters
│ │ └─┬POST
│ │   └──Parameters
│ ├─┬/_mtermvectors
│ │ ├─┬GET
│ │ │ └──Parameters
│ │ └─┬POST
│ │   └──Parameters
│ └─┬/{index}/_termvectors
│   ├─┬GET
│   │ └──Parameters
│   └─┬POST
│     └──Parameters
└─┬Components
  ├──[➕] responses (26383:7)
  ├──[➕] parameters (20246:7)
  ├──[➖] schemas (46741:7)❌ 
  ├──[➖] schemas (46746:7)❌ 
  ├──[➕] schemas (46770:7)
  ├──[➕] schemas (46765:7)
  ├─┬ml._common:UndeployModelResponse
  │ └─┬Schema
  │   └──[🔀] $ref (46765:13)❌ 
  ├─┬_common:VersionNumber
  │ └──[➕] format (29851:15)❌ 
  ├─┬_common:SequenceNumber
  │ └──[➕] format (29534:15)❌ 
  └─┬_common:WriteResponseBase
    └─┬_primary_term
      └──[➕] format (29921:19)❌ 

Document Element	Total Changes	Breaking Changes
components	10	6
paths	1	0

• ❌ BREAKING Changes: 6 out of 11
• Modifications: 1
• Removals: 2
• Additions: 8
• Breaking Removals: 2
• Breaking Modifications: 1
• Breaking Additions: 3

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/10560967101/artifacts/1854722225

API Coverage

	Before	After	Δ
Covered (%)	532 (52.11 %)	533 (52.2 %)	1 (0.09 %)
Uncovered (%)	489 (47.89 %)	488 (47.8 %)	-1 (-0.09 %)
Unknown	26	26	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
559	365 (65.3 %)

[dblock]

Would be nice to exercise DELETE /_plugins/_ml/tasks/{task_id} in a test.

[dblock]

We have some flaky tests I noticed, had to retry. Will track and likely split them from the default test suite run.