Remove unused build configuration file `benchmark/build_config_cc.rb`.
DELETE
benchmark/build_config_cc.rb
-MRuby::Build.new do |conf|
- toolchain :gcc
-end
-
-MRuby::Build.new('gcc') do |conf|
- toolchain :gcc
- conf.gembox 'default'
-end
-
-MRuby::Build.new('clang') do |conf|
- toolchain :clang
- conf.gembox 'default'
-end

Remove unused build configuration file `benchmark/build_config_cc.rb`.