Restore the old behavior of parsing "quote do:"

close #5845

tests/js/tjsffi.nim

@@ -309,11 +309,11 @@ block:
   on("click") do (e: Event):
     console.log e
 
-  jslib.on "reloaded" do:
+  jslib.on("reloaded") do:
     console.log jsarguments[0]
 
   # this test case is different from the above, because
   # `subscribe` is not overloaded in the current scope
-  jslib.subscribe "updates":
+  jslib.subscribe("updates"):
     console.log jsarguments[0]