Update root level README

Signed-off-by: Matthew H. Irby <[email protected]>

Author: irby

README.md

@@ -4,7 +4,7 @@
 
 All instructions in this document are relevant to v1 of the SDK. For information on the latest available SDK (and how to install it), please review the README for that SDK version.
 
-As of writing, the latest available SDK is [version 24](./v24).
+As of writing, the latest available SDK is [version 25](./v25).
 
 # Go API client for keyfactor