pinwheel: Enable rerere in git

hosts/pinwheel/modules/git/default.nix

@@ -17,6 +17,10 @@ in
         includes = [
           { path = ./gitconfig; }
         ];
+
+        extraConfig = {
+          rerere.enable = true;
+        };
       };
 
       home.packages = [ pkgs.tig ];