Update README.md

Author: rcalago

core-java-modules/core-java-io-6/README.md

@@ -6,5 +6,6 @@ This module contains articles about core Java input and output (IO)
 - [Compress and Create a Byte Array Using GZip](https://www.baeldung.com/java-gzip-compress-create-byte-array)
 - [Removing BOM Characters When Reading from File](https://www.baeldung.com/java-remove-byte-order-mask-chars-file)
 - [Clear the Scanner Buffer in Java](https://www.baeldung.com/java-scanner-buffer)
+- [Checking Write Permissions of a Directory in Java](https://www.baeldung.com/java-check-directory-write-permissions)
 - [[<-- Prev]](/core-java-modules/core-java-io-5)