Merge pull request rapid7#19623 from adfoster-r7/fix-kerberos-cache-storage-exception

Fix Kerberos cache storage exception

Author: smcintyre-r7

lib/msf/core/exploit/remote/kerberos/ticket/storage/read_mixin.rb

@@ -9,6 +9,8 @@ def load_credential(options = {})
       available_tickets = tickets(options).select do |ticket|
         !ticket.expired?(now)
       end
+      return unless available_tickets.any?
+
       if options[:offered_etypes].present?
         # Prefer etypes mentioned first
         options[:offered_etypes].each do |etype|