CFG: Don't inject anything when guidance scale doesn't exist

If the guidance scale is 1, completely disable sending CFG and creating
a negative prompt.

Signed-off-by: kingbri <bdashore3@proton.me>

public/scripts/extensions/cfg/index.js

@@ -348,7 +348,7 @@ jQuery(async () => {
             .filter(":checked")
             .map(function() { return parseInt($(this).val()) })
             .get()
-            .filter((e) => e !== NaN) || [];
+            .filter((e) => !Number.isNaN(e)) || [];
 
         chat_metadata[metadataKeys.prompt_combine] = values;
         saveMetadataDebounced();