Add redis roadmap

readme.md

@@ -71,6 +71,7 @@ Here is the list of available roadmaps with more being actively worked upon.
 - [Design System Roadmap](https://roadmap.sh/design-system)
 - [PostgreSQL Roadmap](https://roadmap.sh/postgresql-dba)
 - [SQL Roadmap](https://roadmap.sh/sql)
+- [Redis Roadmap](https://roadmap.sh/redis)
 - [Blockchain Roadmap](https://roadmap.sh/blockchain)
 - [ASP.NET Core Roadmap](https://roadmap.sh/aspnet-core)
 - [System Design Roadmap](https://roadmap.sh/system-design)