Fix deprecation warnings for highlight.js v10.7

[raysonkoh]

While serving a markbind site using markbind serve, I noticed in the outputs there are quite a lot of warnings relating to deprecation warning specifically for the highlight(lang, code, ...args) method of highlight.js. Ref: highlightjs/highlight.js#2277

This might be quite annoying for the users, as showing more than one instance of the deprecation warning may not be useful and the user shouldn't be seeing such deprecation warnings as it is more relevant for the devs. Should we refactor the highlight method in our code to follow the new standard?