Use CX_VERSION variable for cx.js in tinycore.html

tinycore.html

@@ -250,7 +250,7 @@
 	var script = document.createElement('script');
 	script.type = 'text/javascript';
 
-	var cxFile = "https://cheerpxdemos.leaningtech.com/publicdeploy/20221125/cx.js";
+	var cxFile = "https://cheerpxdemos.leaningtech.com/publicdeploy/CX_VERSION/cx.js";
 	script.src = cxFile;
 	script.addEventListener("load", runInit, false);