Fix issue that when run build locally, it throws error about "sed".

[huytunguyenn]

Summary

Currently, if you build docs on your local Mac, there will be some error about the "sed" command in the console. It is not a critical error as it only happens when running the build locally, and the "minify-css.sh" function is just for optimizing CSS so it should not impact the normal render for the pages.

Related PRs, issues, or features (optional)

• N/A

Metadata

• [ ] Adds new file(s)
• [ ] Edits existing file(s)
• [ ] Removes file(s)

PR contributor checklist

• [ ] My PR follows the Kobiton Docs contributor guidelines, meaning:

  • My content contains correct spelling and grammar.
  • My directories and files are named and structured correctly.
  • My style and voice follows the Microsoft Style Guide.
  • I added all new pages to their section's nav.adoc file.
  • I removed all localizations (like en-us) from my URLs.