[ISSUE #33] some thread safety problems

[tianliuliu]

fix #33 fix some thread safety problems

[codecov-commenter]

Codecov Report

Merging #34 (231a7cb) into main (da74925) will decrease coverage by 0.02%.
The diff coverage is 33.33%.

@@            Coverage Diff             @@
##             main      #34      +/-   ##
==========================================
- Coverage   21.59%   21.57%   -0.03%     
==========================================
  Files          87       87              
  Lines        3713     3717       +4     
  Branches      607      609       +2     
==========================================
  Hits          802      802              
- Misses       2696     2698       +2     
- Partials      215      217       +2     

Impacted Files	Coverage Δ
...he/rocketmq/mqtt/cs/session/infly/RetryDriver.java	40.11% <33.33%> (-0.48%)	⬇️
.../apache/rocketmq/mqtt/ds/notify/NotifyManager.java	25.53% <33.33%> (-0.37%)	⬇️

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