Remove broken flake-compat and GApps cruft from nix (#263)

`flake-compat` has been broken for ages probably due to the submodules

Users can instead callPackage `nix/package.nix` if they want to be
flakeless

Author: Coca162

default.nix

@@ -2,10 +2,6 @@
   description = "Flake providing a package for the Space Station 14 Launcher.";
 
   inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
-  inputs.flake-compat = {
-    url = "github:edolstra/flake-compat";
-    flake = false;
-  };
 
   outputs =
     { self, nixpkgs, ... }:

flake.lock

@@ -5,7 +5,6 @@
   buildDotnetModule,
   dotnetCorePackages,
   fetchFromGitHub,
-  wrapGAppsHook3,
   iconConvTools,
   copyDesktopItems,
   makeDesktopItem,
@@ -133,12 +132,6 @@ buildDotnetModule rec {
     icoFileToHiColorTheme SS14.Launcher/Assets/icon.ico space-station-14-launcher $out
   '';
 
-  dontWrapGApps = true;
-
-  preFixup = ''
-    makeWrapperArgs+=("''${gappsWrapperArgs[@]}")
-  '';
-
   meta = with lib; {
     description = "Launcher for Space Station 14, a multiplayer game about paranoia and disaster";
     homepage = "https://spacestation14.io";