add gpg-agent for ubuntu

Author: ltalirz

tasks/debian.yml

@@ -9,6 +9,10 @@
 #	- the CVMFS configuration repository contains the public CVMFS keys for all other Compute Canada CVMFS repositories
 #	- the other CVMFS repositories contain all Compute Canada software (and other content)
 
+- name: Install gpg agent
+  apt:
+    name: [ 'gpg-agent' ]
+
 - name: Install CernVM GPG key
   apt_key:
     url: https://cvmrepo.web.cern.ch/cvmrepo/apt/cernvm.gpg