Update Logstash pipeline create example.

Author: mashhurs

examples/resources/elasticstack_elasticsearch_logstash_pipeline/resource.tf

@@ -34,5 +34,5 @@ EOF
 }
 
 output "pipeline" {
-  value = elasticstack_elasticsearch_logstash_pipeline.example.pipeline_id
+  value = elasticstack_elasticsearch_logstash_pipeline_example_pipeline_id
 }