Add resources for ACID compliance

* Update 101-acid.md

I add some content to ACID on backend roadmap

* Update 101-acid.md

Co-authored-by: Kamran Ahmed <kamranahmed.se@gmail.com>

content/roadmaps/101-backend/content/108-more-about-databases/101-acid.md

@@ -1 +1,7 @@
-# Acid
+# ACID
+
+ACID are the four properties of any database system that help in making sure that we are able to perform the transactions in a reliable manner. It's an acronym which refers to the presence of four properties: atomicity, consistency, isolation and durability 
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink badgeText='Watch' href='https://www.youtube.com/watch?v=yaQ5YMWkxq4'>ACID Explained: Atomic, Consistent, Isolated & Durable</BadgeLink>
+<BadgeLink badgeText='Read' colorScheme='yellow' href='https://retool.com/blog/whats-an-acid-compliant-database/'>What is ACID Compliant Database?</BadgeLink><BadgeLink badgeText='Read' colorScheme='yellow' href='https://fauna.com/blog/what-is-acid-compliance-atomicity-consistency-isolation'>What is ACID Compliance?: Atomicity, Consistency, Isolation</BadgeLink>