[ISSUE #6610] Fix the issue broker startup failed when version upgrade from 5.1.0 to latest develop because compactionThreadNum is 0

[RongtongJin]

Make sure set the target branch to develop

What is the purpose of the change

fix #6610

Brief changelog

Fix the issue broker startup failed when version upgrade from 5.1.0 to latest develop because compactionThreadNum is 0

Verifying this change

XXXX

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[codecov-commenter]

Codecov Report

Merging #6611 (8b63fd9) into develop (ca006ca) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@              Coverage Diff              @@
##             develop    #6611      +/-   ##
=============================================
+ Coverage      43.07%   43.09%   +0.01%     
- Complexity      8988     8993       +5     
=============================================
  Files           1107     1107              
  Lines          78287    78287              
  Branches       10202    10202              
=============================================
+ Hits           33726    33740      +14     
+ Misses         40335    40318      -17     
- Partials        4226     4229       +3     

Impacted Files	Coverage Δ
.../org/apache/rocketmq/store/kv/CompactionStore.java	31.73% <100.00%> (ø)

... and 16 files with indirect coverage changes

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[mxsm]

LGTM~