fix: Index Recovery Keeps an Empty Leaf as Parent Boundary Child

[JacksonYao287]

issue and rca:

https://github.corp.ebay.com/yawzhang/nuobject-test-framework/blob/liveness/test_implementations/storage_hammer/docs/index_repair_links_empty_child_boundary_issue.md

[codecov-commenter]

⚠️ Please install the to ensure uploads and comments are reliably processed by Codecov.

Codecov Report

❌ Patch coverage is 45.83333% with 26 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (stable/v7.x@675dd0a). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
src/include/homestore/index/index_table.hpp	42.22%	8 Missing and 18 partials ⚠️
❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@              Coverage Diff               @@
##             stable/v7.x     #936   +/-   ##
==============================================
  Coverage               ?   48.31%           
==============================================
  Files                  ?      110           
  Lines                  ?    13133           
  Branches               ?     6335           
==============================================
  Hits                   ?     6345           
  Misses                 ?     2555           
  Partials               ?     4233           

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.