tool/gen-mailmap.rb: odaira is removed as he is added in upstream
https://github.com/ruby/ruby-commit-hook/commit/ddc83bea6fe6f4696e140b605db10ef0c922bba6
tool/gen-mailmap.rb: odaira is removed as he is added in upstream
https://github.com/ruby/ruby-commit-hook/commit/ddc83bea6fe6f4696e140b605db10ef0c922bba6