Change pgplex description to governance platform

Updated the description of pgplex to reflect its focus on database governance.

Author: tianzhou

README.md

@@ -1,7 +1,7 @@
 > [!NOTE]
 > pgplex: The Postgres Toolchain for Humans and Agents - **pgconsole** · [pgschema](https://github.com/pgplex/pgschema) · [pgtui](https://github.com/pgplex/pgtui) · [pgparser](https://github.com/pgplex/pgparser)
 > 
-> Brought to you by [Bytebase](https://www.bytebase.com/), open-source database DevSecOps platform.
+> Brought to you by [Bytebase](https://www.bytebase.com/), open-source database Governance platform.
 
 ![](https://raw.githubusercontent.com/pgplex/website/refs/heads/main/public/banner-pgconsole.png)