lyx: clean the expression a bit

Thanks to Sergiu Ivanov <sivanov@colimite.fr>

-2
-2
pkgs/applications/misc/lyx/default.nix
··· 29 30 # python is run during runtime to do various tasks 31 postFixup = '' 32 - sed '1s:/usr/bin/python:${python}/bin/python:' 33 - 34 wrapProgram "$out/bin/lyx" \ 35 --prefix PATH : '${python}/bin' 36 '';
··· 29 30 # python is run during runtime to do various tasks 31 postFixup = '' 32 wrapProgram "$out/bin/lyx" \ 33 --prefix PATH : '${python}/bin' 34 '';