Make git be able to clone into existing empty dirs

Needed if you want to alter the permissions on the directory

scone/default/recipes/filesystem.py

@@ -322,7 +322,7 @@ class GitCheckout(Recipe):
         # no non-arg dependencies
         k.get_dependency_tracker()
 
-        stat = await k.ut1a(Stat(self.dest_dir), Stat.Result)
+        stat = await k.ut1a(Stat(self.dest_dir + "/.git"), Stat.Result)
         if stat is None:
             # doesn't exist; git init it
             await exec_no_fails(k, ["git", "init", self.dest_dir], "/")