EXT-7763 FIXED Made text editor of script error window as read only.

reviewed by Vadim Savchuk at https://codereview.productengine.com/secondlife/r/594/

--HG--
branch : product-engine

indra/newview/skins/default/xui/en/floater_script_debug_panel.xml

@@ -18,6 +18,7 @@
      max_length="2147483647"
      name="Chat History Editor"
      parse_highlights="true" 
+     read_only="true"
      width="420"
      word_wrap="true" />
 </floater>