gh-pages: optimize effect script

Less operations, simpler code.

flake.nix

@@ -54,12 +54,10 @@
               export GIT_COMMITTER_NAME="Hercules-CI Effects"
               export EMAIL="github@croughan.sh"
 
-              mkdir gh-pages && cd gh-pages
+              cp -r --no-preserve=mode ${self.website} ./gh-pages && cd gh-pages
               git init -b gh-pages
               git remote add origin git@github.com:Plutonomicon/plutonomicon.git
-              cp -r ${self.website}/* .
-              cp -r ${self.website}/.nojekyll .
-              git add . .nojekyll
+              git add .
               git commit -m "Deploy to gh-pages"
               git push -f origin gh-pages:gh-pages
             '';