Add backup meta for backupninja

Change-Id: Ifc31ef6e5b946827785873fba4a79a040a7783a0
diff --git a/metadata/service/support.yml b/metadata/service/support.yml
index 09b1d97..5085e28 100644
--- a/metadata/service/support.yml
+++ b/metadata/service/support.yml
@@ -9,3 +9,5 @@
         enabled: false
       sphinx:
         enabled: true
+      backupninja:
+        enabled: true