Fix "Invalid expression" when calling :Spawn on Windows

Author: Vernon Jones

autoload/dispatch/windows.vim

@@ -64,7 +64,7 @@ function! dispatch#windows#start(request) abort
           \ s:pid . pidfile .
           \ ' & ' . a:request.command .
           \ pause .
-          \ ' & cd . > ' . a:request.file.'.complete'
+          \ ' & cd . > ' . a:request.file.'.complete' .
           \ ' & del ' . pidfile
   endif