krb5: new tag krb5-1.15.4-final

[Greg Hudson]

A new lightweight tag "krb5-1.15.4-final" has been created in the krb5
repository for the following commit:

commit ce02c35a2780f0c794e67674060ad11037ecdac0
Author: Greg Hudson <ghudson at mit.edu>
Date:   Thu Nov 1 18:36:44 2018 -0400

    Update for krb5-1.15.4