fetchGit: add submodules attribute to the .link file
fetchGit: add submodules attribute to the .link file

The .link file is used as a lock, so I think we should put the
"submodule" attribute in there since turning on submodules creates a new
.link file path.

rycee/nix,NixOS/nix,NixOS/nix,ehmry/nix,NixOS/nix,rycee/nix,pikajude/nix,ehmry/nix,pikajude/nix,NixOS/nix,ehmry/nix,rycee/nix,ehmry/nix,ehmry/nix,ehmry/nix,rycee/nix,pikajude/nix,NixOS/nix,rycee/nix