It appears you have switched to Laravel. That framework should take care of a lot of security vulnerabilities automatically for you as long as you don't circumvent their procedures. You can of course make your own security vulnerabilities with code, so you should still be mindful of that.
I would argue that #5 and #6 of Master Coder's points are arguably not necessary to change. CDN's are pretty widely used and you are using some reasonably trustworthy sites. The one I might move into your domain specifically is bootstrap.min.js, although it's not a big deal either way.
The point of #6