Update diskann mv UT

[chasingegg]

/kind improvement

[sre-ci-robot]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.00%. Comparing base (3c46f4c) to head (339a065).
Report is 300 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##           main    #1045       +/-   ##
=========================================
+ Coverage      0   73.00%   +73.00%     
=========================================
  Files         0       82       +82     
  Lines         0     7508     +7508     
=========================================
+ Hits          0     5481     +5481     
- Misses        0     2027     +2027     

see 82 files with indirect coverage changes

[PwzXxm]

/lgtm