🐛 fix prometheus init failed when start

[songxiaosheng]

What is the purpose of the change

fix #12321 when simpleclient_pushgateway don't exists cause start failed

Brief changelog

Verifying this change

Checklist

• Make sure there is a GitHub_issue field 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.
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[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

68.8% Coverage
0.0% Duplication

[codecov-commenter]

Codecov Report

Merging #12349 (d713341) into 3.2 (35fdf9d) will decrease coverage by 0.35%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##                3.2   #12349      +/-   ##
============================================
- Coverage     69.68%   69.34%   -0.35%     
+ Complexity      339        2     -337     
============================================
  Files          1828     1607     -221     
  Lines         95300    66267   -29033     
  Branches      17344     9722    -7622     
============================================
- Hits          66407    45950   -20457     
+ Misses        23442    15858    -7584     
+ Partials       5451     4459     -992     

see 3435 files with indirect coverage changes

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