nix: disable checks in regular build

The script will only work after patching, so regular checks don’t work on proper nixos.

flake.nix

@@ -28,12 +28,10 @@
               src = ./.;
               outputs = [ "out" "doc" ];
               buildPhase = ''
+                # Remove the stale VCS copy
+                rm tomono
                 ${myemacs}/bin/emacs --batch --load emacs-docker/init.el --load publish.el
               '';
-              doCheck = true;
-              checkPhase = ''
-                ./tomono --help
-              '';
               installPhase = ''
                 mkdir -p $out/{bin,doc}
                 cp tomono $out/bin/
@@ -42,7 +40,6 @@
                 # the outputs attr on the derivation.
                 cp index.html style.css $out/doc
               '';
-              doInstallCheck = true;
               installCheckPhase = ''
                 $out/bin/tomono --help
               '';
@@ -91,6 +88,7 @@
               self.packages.${system}.default
               pkgs.makeWrapper
             ];
+            doCheck = true;
             checkPhase = ''
               # Ensure we're testing the pre-built tomono derivation, not the new one
               rm -f tomono
@@ -102,7 +100,6 @@
               ./test
             '';
             installPhase = "echo done > $out";
-            doInstallCheck = false;
             dontFixup = true;
           });
         });