fixed duplicate custom&peer.address field

[zxfishhack]

fix #120 #166 , zap will not cleanup duplicate field but logrus will. so can't call ctxzap.TagsToFields() twice.

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[codecov-io]

Codecov Report

Merging #187 into master will decrease coverage by 0.29%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master     #187     +/-   ##
=========================================
- Coverage    73.2%   72.91%   -0.3%     
=========================================
  Files          36       36             
  Lines        1340     1340             
=========================================
- Hits          981      977      -4     
- Misses        310      314      +4     
  Partials       49       49

Impacted Files	Coverage Δ
logging/zap/server_interceptors.go	100% <100%> (ø)	⬆️
retry/retry.go	76.11% <0%> (-2.23%)	⬇️

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[googlebot]

CLAs look good, thanks!

[Crevil]

Anything blocking this PR for merge?

[johanbrandhorst]

Thanks for the reminder :).

[Crevil]

Sweet. Thanks for merging. :D