BUG: index may not monotonic increasing in DataFrameGroupbySortShuffle op

[ChengjieLi28]

What do these changes do?

Related issue number

Fixes #xxxx

Check code requirements

• tests added / passed (if needed)
• Ensure all linting tests pass

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.84%. Comparing base (f67ffd4) to head (1870c35).
⚠️ Report is 64 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #752      +/-   ##
==========================================
- Coverage   93.58%   89.84%   -3.74%     
==========================================
  Files        1058     1058              
  Lines       79780    79783       +3     
  Branches    16504    16506       +2     
==========================================
- Hits        74659    71685    -2974     
- Misses       3446     6250    +2804     
- Partials     1675     1848     +173     

Flag	Coverage Δ
unittests	89.74% <100.00%> (-3.74%)	⬇️

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