fix(datanode): mark the extent as IsDeleted if it exist in deleteExtents map

[yansenliang]

What this PR does / why we need it:
Mark the extent as 'IsDeleted' if it exist in deleteExtents map，no need to add it to deleteExtents.

Which issue this PR fixes:

fixes #

Special notes for your reviewer:

Release note:

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 41.99%. Comparing base (bdffd66) to head (a7bd316).
Report is 29 commits behind head on master.

❗ Current head a7bd316 differs from pull request most recent head bfcfefb. Consider uploading reports for the commit bfcfefb to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3072      +/-   ##
==========================================
+ Coverage   40.49%   41.99%   +1.50%     
==========================================
  Files         603      577      -26     
  Lines      125057   118953    -6104     
==========================================
- Hits        50643    49960     -683     
+ Misses      70051    64722    -5329     
+ Partials     4363     4271      -92     

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