disallow url literals by default

[figsoda]

this is the default behavior for ofborg and hydra: https://github.com/NixOS/ofborg/pull/628

also adds --allow-url-literals

[SuperSandro2000]

What speaks against settings this globally in nix.conf?

[figsoda]

That would require the user to do it, and users don't have to follow nixpkgs conventions for all of their nix projects

[SuperSandro2000]

true but ofborg is also checking it now. Not sure if we really need it but it is a nice addition.

[figsoda]

url literals are probably just supported for the sake of backward compatibility, I'm not sure if there is anything else nixpkgs-review can do to change that

[Mic92]

bors merge

[bors[bot]]

Build succeeded:

• build-flake
• tests