AWS EC2 metrics: use latency option (#547)

Author: mtojek

test/packages/aws/data_stream/ec2_metrics/_dev/test/system/test-default-config.yml

@@ -5,7 +5,8 @@ vars:
   session_token: '{{AWS_SESSION_TOKEN}}'
 data_stream:
   vars:
-    period: 60s
+    period: 5m
+    latency: 10m
     tags_filter: |-
       - key: Name
         value: "elastic-package-test-{{TEST_RUN_ID}}"