[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

Follow this checklist to help us incorporate your contribution quickly and easily. Notice, it would be helpful if you could finish the following 5 checklist(the last one is not necessary)before request the community to review your PR.

• Make sure there is a Github issue filed for the change (usually before you start working on it). Trivial changes like typos do not require a Github issue. Your pull request should address just this issue, without pulling in other changes - one PR resolves one issue.
• Format the pull request title like [ISSUE #123] Fix UnknownException when host config not exist. Each commit in the pull request should have a meaningful subject line and body.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Write necessary unit-test(over 80% coverage) to verify your logic correction, more mock a little better when a cross-module dependency exists.
• If this contribution is large, please file an Apache Individual Contributor License Agreement.

[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%)	⬆️
internal/client.go	0.17% <0.00%> (ø)

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[guyinyou]

approve