vagrant: Specify sync arguments to fix bad defaults

Related vagrant issue: hashicorp/vagrant#5471

Closes cockpit-project#7749

Vagrantfile

@@ -7,7 +7,7 @@ Vagrant.configure(2) do |config|
 
     config.vm.box = "fedora/26-cloud-base"
     config.vm.synced_folder ".", "/vagrant", disabled: true
-    config.vm.synced_folder "./dist", "/cockpit/dist", type: "rsync", create: true
+    config.vm.synced_folder "./dist", "/cockpit/dist", type: "rsync", create: true, rsync__args: ["--verbose", "--archive", "--delete", "-z"]
     config.vm.network "private_network", ip: "192.168.50.10"
     config.vm.network "forwarded_port", guest: 9090, host: 9090
     config.vm.hostname = "cockpit-devel"