nginx: include mimetypes mapping

(cherry picked from commit b01eebf021388d92a8aaba9339dcc1fa2270294d)
Signed-off-by: Domen Kožar <[e-mail]>

nixos/modules/services/web-servers/nginx/default.nix

···
   configFile = pkgs.writeText "nginx.conf" ''
     user ${cfg.user} ${cfg.group};
     daemon off;
+
     ${cfg.config}
+
     ${optionalString (cfg.httpConfig != "") ''
     http {
+      include ${cfg.package}/conf/mime.types;
       ${cfg.httpConfig}
     }
     ''}