Update ctr so it works again on windows

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>

server/server_unsupported.go

@@ -1,9 +1,16 @@
-// +build !linux
+// +build !linux,!windows
 
 package server
 
 import "context"
 
+const (
+	// DefaultAddress is the default unix socket address
+	DefaultAddress = "/run/containerd/containerd.sock"
+	// DefaultDebuggAddress is the default unix socket address for pprof data
+	DefaultDebugAddress = "/run/containerd/debug.sock"
+)
+
 func apply(_ context.Context, _ *Config) error {
 	return nil
 }