Interpolate variables in the MDX

Thank you all for Docusaurus, it’s really easy and understandable 🙌

💥 Proposal

Following the https://github.com/facebook/docusaurus/issues/395#issuecomment-925703543 we are really need ability to interpolate variables in MDX markup of *.md files.

For example:

const data = "azaza";

// we wish this:
'''jsx
  const data = "{data}";
'''

// to become:
'''jsx
  const data = "azaza";
'''

[JasonZhLiang]

@slorber thanks a lot, you save my day!

[slorber]

No official example I actually tried to share but I guess this could be an example: https://github.com/angeloashmore/gatsby-remark-find-replace/blob/master/src/index.js

(just found this with Google)