best-practices: add a new guide on mastering partitioned tables (#21846) (#22348)

Author: ti-chi-bot

TOC.md

@@ -440,6 +440,7 @@
   - [Optimize Multi-Column Indexes](/best-practices/multi-column-index-best-practices.md)
   - [Manage Indexes and Identify Unused Indexes](/best-practices/index-management-best-practices.md)
   - [Handle Millions of Tables in SaaS Multi-Tenant Scenarios](/best-practices/saas-best-practices.md)
+  - [Use TiDB Partitioned Tables](/best-practices/tidb-partitioned-tables-best-practices.md)
   - [Use UUIDs as Primary Keys](/best-practices/uuid.md)
   - [Develop Java Applications](/best-practices/java-app-best-practices.md)
   - [Handle High-Concurrency Writes](/best-practices/high-concurrency-best-practices.md)