Pin osm bundle in charmed installer

Change-Id: I4777fa038ceb2624a20a6bd182f14b5546b58d59
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/installers/charmed_install.sh b/installers/charmed_install.sh
index 00e4112..095c04f 100755
--- a/installers/charmed_install.sh
+++ b/installers/charmed_install.sh
@@ -238,7 +238,7 @@
     if [ -v BUNDLE ]; then
         juju deploy $BUNDLE --overlay ~/.osm/vca-overlay.yaml $images_overlay
     else
-        juju deploy cs:osm --channel edge --overlay ~/.osm/vca-overlay.yaml $images_overlay
+        juju deploy cs:osm-52 --overlay ~/.osm/vca-overlay.yaml $images_overlay
     fi
 
     echo "Waiting for deployment to finish..."