Fix 7z path

[kdheepak]

Fixes #52

[codecov-io]

Codecov Report

Merging #53 into master will increase coverage by 0.03%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master      #53      +/-   ##
==========================================
+ Coverage   69.33%   69.37%   +0.03%     
==========================================
  Files          45       45              
  Lines        2795     2798       +3     
==========================================
+ Hits         1938     1941       +3     
  Misses        857      857

Impacted Files	Coverage Δ
src/utils.jl	69.35% <50%> (+1.55%)	⬆️

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