XF 1.5 Serve resources from a consistent URL

[Betclever]

Hello!

I have 2 times a call to maxcdn when I perform a test with Gt-metrix
How can I remove one cause I don't know where it is?

The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 26.1KiB.

• http://maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.css
• https://maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.css

Thanks.