(Feature request) Code Block language support for Terraform (HCL)

[Hion-V]

Describe feature

It would be nice to have Code Note language support and syntax highlighting for HCL which is used for terraform.

Additional Information

There appears to be a highlightjs package for this already according to https://highlightjs.readthedocs.io/en/latest/supported-languages.html so this might not be too difficult to implement
Also noteworthy is that there's a package for CodeMirror too https://github.com/haoqixu/codemirror-lang-hcl

[eliandoran]

@Hion-V , for now we can only have syntax highlight for code blocks and not code notes (w/ CodeMirror). The reason is that we are currently using CodeMirror 5 but the provided plugin is for CodeMirror 6.

Will create a separate issue to track the code note support.

[eliandoran]

See #771.