Added template fucntion to escape string before output

[rahul2393]

Unescaped strings like https://gist.github.com/simar7/da144ed1d9b6d53f5c9af1e9282a3e68#file-gistfile1-txt-L81-L84 in output SARIF results in invalid SARIF file, this PR will fix the case

[codecov]

Codecov Report

Merging #583 into master will increase coverage by 0.06%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #583      +/-   ##
==========================================
+ Coverage   55.78%   55.84%   +0.06%     
==========================================
  Files          44       44              
  Lines        2110     2113       +3     
==========================================
+ Hits         1177     1180       +3     
  Misses        810      810              
  Partials      123      123              

Impacted Files	Coverage Δ
pkg/report/writer.go	67.70% <100.00%> (+1.04%)	⬆️

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