Update package_gssproxy_removed based on feedback

Author: Mab879

linux_os/guide/system/software/system-tools/package_gssproxy_removed/rule.yml

@@ -8,6 +8,8 @@ description: |-
 
 rationale: |-
     <tt>gssproxy</tt> is a proxy for GSS API credential handling.
+    Kerberos relies some key derivation functions that may not
+    be compatible with some site policies such as FIPS 140.
 
 severity: medium