Hello,
there is no built-in support to add custom content to header section of the website. Only way is to do it directly in source files. The one that you want to modify is "<website_root>/Orion/OrionMinReqs.master". Find <meta> tag in <head> and modify it to desired value. However this is not supported and Orion website will not work properly after this change. If you do the change, check the website look and functionality and decide if it's acceptable for you.