ci: use the specified version of `skywalking`. (#3698)

diff --git a/.github/workflows/centos7-ci.yml b/.github/workflows/centos7-ci.yml
index 8fa110b..1e3b5fc 100644
--- a/.github/workflows/centos7-ci.yml
+++ b/.github/workflows/centos7-ci.yml
@@ -76,7 +76,7 @@
         sleep 5
         docker exec -i kafka-server1 /opt/bitnami/kafka/bin/kafka-topics.sh --create --zookeeper zookeeper-server:2181 --replication-factor 1 --partitions 1 --topic test2
         docker exec -i kafka-server1 /opt/bitnami/kafka/bin/kafka-topics.sh --create --zookeeper zookeeper-server:2181 --replication-factor 1 --partitions 3 --topic test3
-        docker run --rm --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 apache/skywalking-oap-server
+        docker run --rm --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 apache/skywalking-oap-server:8.3.0-es6
         docker run --rm --name consul_1 -d -p 8500:8500 consul:1.7 consul agent -server -bootstrap-expect=1 -client 0.0.0.0 -log-level info -data-dir=/consul/data
         docker run --rm --name consul_2 -d -p 8600:8500 consul:1.7 consul agent -server -bootstrap-expect=1 -client 0.0.0.0 -log-level info -data-dir=/consul/data
 
diff --git a/.travis/linux_openresty_common_runner.sh b/.travis/linux_openresty_common_runner.sh
index 6bc2821..bb2b254 100755
--- a/.travis/linux_openresty_common_runner.sh
+++ b/.travis/linux_openresty_common_runner.sh
@@ -38,7 +38,7 @@
     docker exec -i kafka-server1 /opt/bitnami/kafka/bin/kafka-topics.sh --create --zookeeper zookeeper-server:2181 --replication-factor 1 --partitions 3 --topic test3
 
     # start skywalking
-    docker run --rm --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 apache/skywalking-oap-server
+    docker run --rm --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 apache/skywalking-oap-server:8.3.0-es6
     # start consul servers
     docker run --rm --name consul_1 -d -p 8500:8500 consul:1.7 consul agent -server -bootstrap-expect=1 -client 0.0.0.0 -log-level info -data-dir=/consul/data
     docker run --rm --name consul_2 -d -p 8600:8500 consul:1.7 consul agent -server -bootstrap-expect=1 -client 0.0.0.0 -log-level info -data-dir=/consul/data
diff --git a/docs/en/latest/plugins/skywalking.md b/docs/en/latest/plugins/skywalking.md
index a9eee4d..6475fad 100644
--- a/docs/en/latest/plugins/skywalking.md
+++ b/docs/en/latest/plugins/skywalking.md
@@ -113,7 +113,7 @@
     - By default, use H2 storage, start skywalking directly
 
         ```shell
-        sudo docker run --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 --restart always apache/skywalking-oap-server
+        sudo docker run --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 --restart always apache/skywalking-oap-server:8.3.0-es6
         ```
 
     - Of Course, you can use Elasticsearch storage
@@ -133,7 +133,7 @@
         3. Run skywalking server:
 
             ```shell
-            sudo docker run --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 --restart always --link elasticsearch:elasticsearch -e SW_STORAGE=elasticsearch -e SW_STORAGE_ES_CLUSTER_NODES=elasticsearch:9200 apache/skywalking-oap-server
+            sudo docker run --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 --restart always --link elasticsearch:elasticsearch -e SW_STORAGE=elasticsearch -e SW_STORAGE_ES_CLUSTER_NODES=elasticsearch:9200 apache/skywalking-oap-server:8.3.0-es6
             ```
 
 2. Skywalking WebUI:
diff --git a/docs/zh/latest/plugins/skywalking.md b/docs/zh/latest/plugins/skywalking.md
index 2c68351..888a0d3 100644
--- a/docs/zh/latest/plugins/skywalking.md
+++ b/docs/zh/latest/plugins/skywalking.md
@@ -117,7 +117,7 @@
     - 默认使用 H2 存储,直接启动 skywalking 即可
 
         ```shell
-        sudo docker run --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 --restart always apache/skywalking-oap-server
+        sudo docker run --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 --restart always apache/skywalking-oap-server:8.3.0-es6
         ```
 
     - 如果使用 Elasticsearch 存储
@@ -136,7 +136,7 @@
         3. 启动 skywalking:
 
             ```shell
-            sudo docker run --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 --restart always --link elasticsearch:elasticsearch -e SW_STORAGE=elasticsearch -e SW_STORAGE_ES_CLUSTER_NODES=elasticsearch:9200 apache/skywalking-oap-server
+            sudo docker run --name skywalking -d -p 1234:1234 -p 11800:11800 -p 12800:12800 --restart always --link elasticsearch:elasticsearch -e SW_STORAGE=elasticsearch -e SW_STORAGE_ES_CLUSTER_NODES=elasticsearch:9200 apache/skywalking-oap-server:8.3.0-es6
             ```
 
 2. Skywalking 管理系统: