test(modules): Check eval is identical to nixpkgs

We want these modules to be importable by people, as a set, even if they
don't want to use all of the options or import all of the dependencies

This test makes sure of 2 things
- Our modules can be evaluated on the default configuration with only
  stuff that is permitted in our README
- Without some configuration, our modules do not change the outputted
  system toplevel

This can be used as a rough proxy for being "safe to import", as
hopefully these modules won't introduce any changes to your config from
only an import

Change-Id: Ied99c3460a76f205de1724db2c531723cc3506b5
Reviewed-on: https://git.clicks.codes/c/Infra/NixFiles/+/812
Reviewed-by: Skyler Grey <minion@clicks.codes>
Tested-by: Skyler Grey <minion@clicks.codes>
diff --git a/lib/checks/default.nix b/lib/checks/default.nix
index 0340be1..9a21b20 100644
--- a/lib/checks/default.nix
+++ b/lib/checks/default.nix
@@ -29,6 +29,7 @@
           --eval-store $HOME \
           --flake \
           --option extra-experimental-features flakes \
+          --show-trace \
           ${inputPathArgs} \
           .#specs.${pkgs.system}
         touch $out