Add Elasticsearch SSL support to fluentd

Change-Id: Ia74868f4b009f6bd4e8af0c812e7a1e75dff0a85
PROD-related: PROD-29185
diff --git a/metadata/service/agent/single.yml b/metadata/service/agent/single.yml
index b4ea1c1..38eda02 100644
--- a/metadata/service/agent/single.yml
+++ b/metadata/service/agent/single.yml
@@ -9,3 +9,4 @@
       enabled: true
       dir:
         positiondb: /var/lib/fluentd/positiondb
+        config: /etc/td-agent