Fix bug 2145: Wrong VCA data in new sidecar MON charm

Change-Id: Ib24c54cffd158f6ae4397311becc3769a1cce543
Signed-off-by: Guillermo Calvino <guillermo.calvino@canonical.com>

installers/charm/osm-mon/src/charm.py

@@ -245,9 +245,9 @@ class OsmMonCharm(CharmBase):
         }
         if self.vca.data:
             environment["OSMMON_VCA_HOST"] = self.vca.data.endpoints
-            environment["OSMMON_VCA_SECRET"] = self.vca.secret
-            environment["OSMMON_VCA_USER"] = self.vca.user
-            environment["OSMMON_VCA_CACERT"] = self.vca.cacert
+            environment["OSMMON_VCA_SECRET"] = self.vca.data.secret
+            environment["OSMMON_VCA_USER"] = self.vca.data.user
+            environment["OSMMON_VCA_CACERT"] = self.vca.data.cacert
         return {
             "summary": "mon layer",
             "description": "pebble config layer for mon",