Fix installation and security issues

[MatheusCamelucci]

Hi everyone!

This PR should fix the issues below:

1. Installation fails due the "node-sass" deprecated version, as seen in Unable to install spectacle via npm #234
2. Updated jQuery to latest version and replaced the old links with the Cloudflare CDN ones, as seen in Update jquery and leverage SRI #228

Other changes and improvements:

1. NodeJS support changed from v8 to v18
2. Updated Foundation to one of the latest versions (v6.7.5)
3. Fixed some code issues with the "marked" and "highlight.js" libraries due to my last PR in 2021, as seen in Fix code bugs and update dependencies #224
   • See e2165fd for more details, where line 51 of "app/lib/common.js" returns undefined due the "marked" update in 0802dec

With these updates I think we could add some extra lifetime to Spectacle, but I would like to warn about some points:

1. Some libraries, like "chai", started to support only EcmaScript Modules (ESM) and this can be a problem since Spectacle uses the old CommonJS Modules
2. Foundation is another library that I could not update to latest version due the incompatibility, I needed to manually "fix" the source code so it can be compatible with the latest version of jQuery

🧪 The code passed in all tests ✅

Sorry if my text have some grammatical mistakes

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🎉 Happy 2024! 🎉