ST-1325 bump umbrella chart to 0.3.15

charts/ska-tango-umbrella/Chart.yaml

@@ -6,10 +6,10 @@ version: 0.2.5
 icon: https://www.skatelescope.org/wp-content/uploads/2016/07/09545_NEW_LOGO_2014.png
 dependencies:
 - name: ska-tango-base
-  version: 0.3.14
+  version: 0.3.15
   repository: file://../ska-tango-base
   condition: ska-tango-base.enabled,global.sub-system.ska-tango-base.enabled
 - name: ska-tango-util
-  version: 0.3.14
+  version: 0.3.15
   repository: file://../ska-tango-util