[RU] Update ecto/associations.md to 1.2.1
[RU] Update ecto/associations.md to 1.2.1

1.2.0: c2d32990d8db73349680d9cf6c0bc19dc2534509
1.2.1: n/a

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