[JA] Translate plug 2.2.0 (#1903)
[JA] Translate plug 2.2.0 (#1903)

* translate JA plug 2.2.0

* not translate `child spec`

* all translated

* fix typo

* Update ja/lessons/specifics/plug.md

Co-Authored-By: Shia <560aa40894f3626ca390fdc86b663ac7538e62af@gmail.com>

* Update ja/lessons/specifics/plug.md

Co-Authored-By: Shia <560aa40894f3626ca390fdc86b663ac7538e62af@gmail.com>

* Update ja/lessons/specifics/plug.md

Co-Authored-By: Shia <560aa40894f3626ca390fdc86b663ac7538e62af@gmail.com>

nscyclone/elixir-school,nscyclone/elixir-school,doomspork/elixir_school,nscyclone/elixir-school,nscyclone/elixir-school,doomspork/elixir-school,doomspork/elixir_school,doomspork/elixir-school,doomspork/elixir_school,doomspork/elixir-school