fix: 解决健康检查规则打印时候出现的协程panic问题

[andrewshan]

fix: 修复健康检查规则报错问题

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Fixes #

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• HealthCheck
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[codecov]

Codecov Report

Merging #1024 (f011153) into release-v1.15.0 (248df93) will increase coverage by 0.55%.
The diff coverage is 100.00%.

@@                 Coverage Diff                 @@
##           release-v1.15.0    #1024      +/-   ##
===================================================
+ Coverage            57.26%   57.82%   +0.55%     
===================================================
  Files                  190      190              
  Lines                34379    34381       +2     
===================================================
+ Hits                 19688    19880     +192     
+ Misses               12120    11911     -209     
- Partials              2571     2590      +19     

Impacted Files	Coverage Δ
cache/faultdetect.go	63.72% <ø> (+45.66%)	⬆️
service/healthcheck/server.go	30.81% <100.00%> (+1.22%)	⬆️

... and 12 files with indirect coverage changes

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