Add the new newsletter site

[YoshithaRathnayake]

Purpose

The purpose of this PR is to fix #455

Goals

Adding the newsletter site to the sack-site

Approach

I added the newsletter site to the sack-site

Screenshots

Preview Link

https://pr-454-sack-site-acf.surge.sh/newsletter

Checklist

• This PR doesn't commit any keys, passwords, tokens, usernames, or other secrets.
• I have read and understood the development best practices guidelines
• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation

Related PRs

Test environment

Learning