Make indices.get_mapping::query.index not required

[nhtruong]

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[github-actions]

Changes Analysis

Commit SHA: 10949d6
Comparing To SHA: c6fbaf9

API Changes

Summary

└─┬Paths
  ├─┬/{index}/_mapping
  │ └─┬GET
  │   └─┬Parameters
  │     └──[➖] required (16593:17)❌ 
  └─┬/_mapping
    └─┬GET
      └─┬Parameters
        └──[➖] required (16593:17)❌ 

Document Element	Total Changes	Breaking Changes
paths	2	2

• ❌ BREAKING Changes: 2 out of 2
• Removals: 2
• Breaking Removals: 2

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/9899678604/artifacts/1693160180

API Coverage

	Before	After	Δ
Covered (%)	483 (47.31 %)	483 (47.31 %)	0 (0 %)
Uncovered (%)	538 (52.69 %)	538 (52.69 %)	0 (0 %)
Unknown	24	24	0