[KO] Fixed wrong-translated words in OTP Concurrency lesson (#581)
[KO] Fixed wrong-translated words in OTP Concurrency lesson (#581)

* Fix typo

Note -> 참고
atom -> 애텀

* Eliminate awkward character

ㄹ??

* Fix wrong-translated words

doomspork/elixir_school,ElixirVietnam/elixir-school,erickgnavar/elixir-school,holsky/elixir-school,yuriibodarev/elixir-school,erickgnavar/elixir-school,doomspork/elixir_school,yuriibodarev/elixir-school,psantos10/elixir-school,doomspork/elixir-school,huydx/elixir-school,yuriibodarev/elixir-school,erickgnavar/elixir-school,doomspork/elixir-school,psantos10/elixir-school,doomspork/elixir-school,huydx/elixir-school,nscyclone/elixir-school,doomspork/elixir_school,ElixirVietnam/elixir-school,holsky/elixir-school,holsky/elixir-school,nscyclone/elixir-school,ElixirVietnam/elixir-school,psantos10/elixir-school,huydx/elixir-school,nscyclone/elixir-school,nscyclone/elixir-school