Mentioned Markdown flavor in Contribution new content

Signed-off-by: Siddhant Prateek <[email protected]>

Author: siddhantprateek

content/en/docs/contribute/new-content/_index.md

@@ -56,12 +56,14 @@ prior to submitting new content. The information details follow.
 
 - Write Kubernetes documentation in Markdown and build the Kubernetes site
   using [Hugo](https://gohugo.io/).
+- Kubernetes documentation uses [CommonMark](https://commonmark.org/) as its flavor of  Markdown. 
 - The source is in [GitHub](https://github.com/kubernetes/website). You can find
   Kubernetes documentation at `/content/en/docs/`. Some of the reference
   documentation is automatically generated from scripts in
   the `update-imported-docs/` directory.
 - [Page content types](/docs/contribute/style/page-content-types/) describe the
   presentation of documentation content in Hugo.
+- You can use [Docsy shortcodes](https://www.docsy.dev/docs/adding-content/shortcodes/) or our custom Hugo shortcode to contribute to our documentation.
 - In addition to the standard Hugo shortcodes, we use a number of
   [custom Hugo shortcodes](/docs/contribute/style/hugo-shortcodes/) in our
   documentation to control the presentation of content.