mod_http: Fix error if 'access_control_allow_origins' is set Because it changes the type of the 'opt_origins' variable from util.set to the internal _items table so next time an http app is added an error "attempt to call a nil value (method 'empty')" is triggered. The value is not used anywhere else. Noticed when reviewing uses of the '_items' set property. Not reported by any users, implying this setting is rarely used.

--- a/plugins/mod_http.lua	Sat Jun 10 12:14:12 2023 +0200
+++ b/plugins/mod_http.lua	Sat Jun 10 12:33:58 2023 +0200
@@ -149,7 +149,7 @@
 		local app_credentials = opt_credentials;
 		local app_origins;
 		if opt_origins and not (opt_origins:empty() or opt_origins:contains("*")) then
-			opt_origins = opt_origins._items;
+			app_origins = opt_origins._items;
 		end
 
 		local function cors_handler(event_data)