Add a note about Box connector limitation

docs/tutorials/box/box.md

@@ -6,6 +6,8 @@ The below diagram describes the scenario. In this scenario, `employee.csv` CSV f
 to a target CSV file called, `employee.csv` inside a target folder. Note that any other type of connection (such as S3, database etc.) can be 
 used interchangeably with the Box connector.
 
+**Note note that Box connector only supports `.CSV` files.**
+
 ![Using Box connector to move a file.](images/BoxConnectorScenario.svg)
 
 The diagram source can be found [here](https://app.lucidchart.com/documents/edit/77f36467-4d01-4ed8-802a-c2ec3d97738e/0_0?beaconFlowId=26DFD7EF970567C0).