Add workflow using lychee to ensure that links in documentation files resolve

[cwperks]

Description

This workflow is already present across many repos in the OpenSearch project, but its missing from this repo.

This PR adds a PR check to ensure that links in the codebase resolve successfully.

• Category (Enhancement, New feature, Bug fix, Test fix, Refactoring, Maintenance, Documentation)

Maintenance

Issues Resolved

Resolves: #5347

Check List

• New functionality includes testing
• New functionality has been documented
• New Roles/Permissions have a corresponding security dashboards plugin PR
• API changes companion pull request created
• Commits are signed per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.96%. Comparing base (d7435f0) to head (bd8f053).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5348      +/-   ##
==========================================
+ Coverage   71.90%   71.96%   +0.06%     
==========================================
  Files         378      378              
  Lines       23562    23562              
  Branches     3630     3630              
==========================================
+ Hits        16942    16957      +15     
+ Misses       4810     4794      -16     
- Partials     1810     1811       +1     

see 7 files with indirect coverage changes

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