Remove executable bit for output file

[crvv]

The output Go file is not executable, so I think the executable bit should be removed.

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This change is 

[codecov]

Codecov Report

Merging #245 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #245   +/-   ##
=======================================
  Coverage   80.79%   80.79%           
=======================================
  Files         134      134           
  Lines        5328     5328           
=======================================
  Hits         4305     4305           
  Misses        834      834           
  Partials      189      189

Impacted Files	Coverage Δ
main.go	52.66% <100%> (ø)	⬆️

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[elliotchance]

Reviewed 1 of 1 files at r1.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable

[elliotchance]

Thanks! https://github.com/elliotchance/c2go/releases