[feat] incr instanceCount in once and fmt codes

[aireet]

What is the purpose of the change

i think we should incr instanceCount once, if we Start a consumer more than one times, instanceCount will increase one times, in the case, rmqClient.ShutDown will never work

Brief changelog

XX

Verifying this change

XXXX

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[codecov-commenter]

Codecov Report

Merging #888 (693a6d1) into master (ffd7241) will increase coverage by 0.00%. The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master     #888   +/-   ##
=======================================
  Coverage   25.28%   25.29%           
=======================================
  Files          51       51           
  Lines        6687     6686    -1     
=======================================
  Hits         1691     1691           
  Misses       4769     4769           
+ Partials      227      226    -1     

Impacted Files	Coverage Δ
consumer/consumer.go	17.68% <ø> (+0.03%)	:arrow_up:
internal/client.go	0.17% <0.00%> (ø)

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