fix(elixir-ls): substitute call to `elixir` in launchers (#349988)

    substitute release/debug_adapter.sh $out/bin/elixir-debug-adapter \

      --replace 'exec "''${dir}/launch.sh"' "exec $out/lib/launch.sh"

    chmod +x $out/bin/elixir-debug-adapter

    # prepare the launcher

    # prepare the launchers

    substituteInPlace $out/lib/launch.sh \

      --replace "ERL_LIBS=\"\$SCRIPTPATH:\$ERL_LIBS\"" \

                "ERL_LIBS=$out/lib:\$ERL_LIBS" \

      --replace "exec elixir" "exec ${elixir}/bin/elixir" \

      --replace 'echo "" | elixir' "echo \"\" | ${elixir}/bin/elixir"

    substituteInPlace $out/lib/exec.zsh \

      --replace "exec elixir" "exec ${elixir}/bin/elixir"

    runHook postInstall

  '';