Yes our friends from China invented a new type of DDOS attack. The great firewall changed unencrypted traffic that contained 3rd party javascript libraries to DDOS GitHub.
There is already a testing tool SRI Test developed and deployed by Gabor Szathmari see for more details his blog
To protect my blog I found out that there is already a plugin developed for WordPress that takes care of this issue.
After installing the plugin my blog site went from an F (Rate 50%) score to a better B (Rate: 87.5%) score. See here