Removed unneeded file read to string for Nim JSON test
Removed unneeded file read to string for Nim JSON test

chalucha/benchmarks,kostya/benchmarks,kostya/benchmarks,chalucha/benchmarks,kostya/benchmarks,kostya/benchmarks,kostya/benchmarks,kostya/benchmarks,chalucha/benchmarks,chalucha/benchmarks,kostya/benchmarks,kostya/benchmarks,chalucha/benchmarks,chalucha/benchmarks,kostya/benchmarks,chalucha/benchmarks,kostya/benchmarks,kostya/benchmarks,chalucha/benchmarks,chalucha/benchmarks,kostya/benchmarks,chalucha/benchmarks,kostya/benchmarks,kostya/benchmarks,chalucha/benchmarks,chalucha/benchmarks