Save failures.csv in --no-web mode

[ajt89]

#1237

[codecov]

Codecov Report

Merging #1245 into master will increase coverage by 0.17%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1245      +/-   ##
==========================================
+ Coverage   78.49%   78.66%   +0.17%     
==========================================
  Files          20       20              
  Lines        2004     2006       +2     
  Branches      316      316              
==========================================
+ Hits         1573     1578       +5     
+ Misses        354      351       -3     
  Partials       77       77

Impacted Files	Coverage Δ
locust/stats.py	85.77% <100%> (+1.42%)	⬆️
locust/core.py	92.18% <0%> (-1.24%)	⬇️

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[cyberw]

Thanks! Is there a test that covers this? Would you consider adding one? Just checking the existence of the files is enough.

[schorba]

Thank you a lot !

[vstepanov-lohika-tix]

Very useful update, thanks