Fix minor issue with permissions in Charmed Installer

Change-Id: I53068cdbfd15e357d25cb18c2c5435a69601824f
Signed-off-by: David Garcia <david.garcia@canonical.com>

installers/charmed_install.sh

@@ -51,7 +51,7 @@ function check_arguments(){
 function install_snaps(){
     if [ ! -v KUBECFG ]; then
         sudo snap install microk8s --classic --channel=${MICROK8S_VERSION}/stable
-        cat /var/snap/microk8s/current/args/kube-apiserver | grep advertise-address || (
+        sudo cat /var/snap/microk8s/current/args/kube-apiserver | grep advertise-address || (
                 echo "--advertise-address $DEFAULT_IP" | sudo tee -a /var/snap/microk8s/current/args/kube-apiserver
                 microk8s.stop
                 microk8s.start