Disqus loads it's embed config.js from its root domain
(https://disqus.com). Our CSPs only allow subdomains (e.g.:
https://codimd.disqus.com). This causes the disqus embedding to fail.
This patch should fix this problem by adding https://disqus.com to the
CSP setting. From a security perspective there is no real change. Since
still the same parties are involved.
Signed-off-by: Sheogorath <sheogorath@shivering-isles.com>
ecee16bd73