Bump elasticsearch version

Author: Rockin2

travis/run_es_docker.sh

@@ -1,5 +1,5 @@
 #!/bin/sh
-ES_VERSION="7.6.0"
+ES_VERSION="7.9.2"
 
 docker pull docker.elastic.co/elasticsearch/elasticsearch-oss:${ES_VERSION}
 docker network create esnet-oss;
@@ -14,4 +14,4 @@ docker run \
   --name=elasticsearch-oss \
   --detach \
   docker.elastic.co/elasticsearch/elasticsearch-oss:${ES_VERSION}
-docker run --network esnet-oss --rm appropriate/curl --max-time 120 --retry 120 --retry-delay 1 --retry-connrefused --show-error --silent http://elasticsearch-oss:9200
+docker run --network esnet-oss --rm appropriate/curl --max-time 120 --retry 120 --retry-delay 1 --retry-connrefused --show-error --silent http://elasticsearch-oss:9200