There was an error in the upload process that resulted in an older build being published. That has been fixed now. If you had manually downloaded NDK r25 beta 1 prior to now, you should redownload the correct version.
To confirm that you have the correct version, check the Pkg.Revision field in $NDK/source.properties. It should say 25.0.8151533-beta1. If it says 25.0.8141415-beta1, you have the wrong version and should redownload.