Fix cycle tag

- `respond_to?` was returning `false` in the parser switcher
     because `rigid_parse` was private
     It was working before because `parse_context` was doing
     the double-parsing thing, but when we removed that, this
     test fairly started breaking

lib/liquid/tags/cycle.rb

@@ -52,8 +52,6 @@ module Liquid
       output
     end
 
-    private
-
     # cycle [name:] expression(, expression)*
     def rigid_parse(markup)
       p = @parse_context.new_parser(markup)
@@ -73,6 +71,8 @@ module Liquid
       raise_syntax_error(options) if @variables.empty?
     end
 
+    private
+
     # Temporarily until we migrate
     def strict_parse(markup)
       lax_parse(markup)