Add ETL project link to README (#2087)

Author: imor

README.md

@@ -98,6 +98,7 @@ The Apache Iceberg community is built on the principles described in the [Apache
 - [Moonlink](https://github.com/Mooncake-Labs/moonlink): A Rust library that enables sub-second mirroring (CDC) of Postgres tables into Iceberg.
 - [RisingWave](https://github.com/risingwavelabs/risingwave): A Postgres-compatible SQL database designed for real-time event streaming data processing, analysis, and management.
 - [Wrappers](https://github.com/supabase/wrappers): Postgres Foreign Data Wrapper development framework in Rust.
+- [ETL](https://github.com/supabase/etl): Stream your Postgres data anywhere in real-time.
 
 ## License