docs -- added data handlers that have data catalog (#11860)

Author: martyna-mindsdb

docs/data_catalog/integrations/overview.mdx

@@ -8,6 +8,10 @@ As of now, the Data Catalog is available for the following integrations:
 - [Snowflake](/integrations/data-integrations/snowflake)
 - [Salesforce](/integrations/app-integrations/salesforce)
 - [BigQuery](/integrations/data-integrations/google-bigquery)
+- [MS SQL Server](/integrations/data-integrations/microsoft-sql-server)
+- [MySQL](/integrations/app-integrations/mysql)
+- [Oracle](/integrations/data-integrations/oracle)
+- [PostgreSQL](/integrations/data-integrations/postgresql)
 
 ### Enabling the Data Catalog