[Backport 1.x] Update links to documentation in rest-api-spec

[cwperks]

Description

Backports #13043 to 1.x

This updates all of the links to make them version-specific to the 1.x line. Some of the links had changed on the documentation website, but most links remain the same and only replace latest with 1.3. The ingest API routes are different on the documentation website between 1.3 and latest.

i.e.

https://opensearch.org/docs/latest/ingest-pipelines/create-ingest/ on main

vs

https://opensearch.org/docs/1.3/api-reference/ingest-apis/create-update-ingest/ on 1.3

Related Issues

Resolves #1339

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Failing checks are inspected and point to the corresponding known issue(s) (See: Troubleshooting Failing Builds)
• Commits are signed per the DCO using --signoff
• Commit changes are listed out in CHANGELOG.md file (See: Changelog)
• Public documentation issue/PR created

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[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: SUCCESS ✅
• URL: https://build.ci.opensearch.org/job/gradle-check/36394/
• CommitID: 6ca6863

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.54%. Comparing base (3b4474e) to head (6ca6863).

Additional details and impacted files

@@             Coverage Diff              @@
##                1.x   #13059      +/-   ##
============================================
+ Coverage     77.49%   77.54%   +0.04%     
- Complexity    58734    58760      +26     
============================================
  Files          4223     4223              
  Lines        253567   253567              
  Branches      38700    38700              
============================================
+ Hits         196512   196638     +126     
+ Misses        41025    40922     -103     
+ Partials      16030    16007      -23     

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