Update nginx to 1.15.2

[aledbf]

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[codecov-io]

Codecov Report

Merging #2872 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2872      +/-   ##
==========================================
- Coverage   47.56%   47.54%   -0.02%     
==========================================
  Files          76       76              
  Lines        5483     5483              
==========================================
- Hits         2608     2607       -1     
- Misses       2540     2542       +2     
+ Partials      335      334       -1

Impacted Files	Coverage Δ
internal/watch/file_watcher.go	80.76% <0%> (-3.85%)	⬇️

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