Current Behavior

As mentiond in documentation https://apisix.apache.org/docs/apisix/plugins/skywalking-logger/, when service_instance_name set to $hostname, the plugin will use APISIX hostname to instance name, but it not work now.

Expected Behavior

When setting service_instance_name to $hostname, APISIX must correctly send the hostname as the instance name to skywalking.

Error Logs

No response

Steps to Reproduce

1. Code in skywalking tracer plugin: https://github.com/apache/apisix/blob/master/apisix/plugins/skywalking.lua#L130-L132
2. There is no such code in skywalking-logger.

Environment

• APISIX version (run apisix version): master
• Operating system (run uname -a): not required
• OpenResty / Nginx version (run openresty -V or nginx -V): not required
• etcd version, if relevant (run curl http://127.0.0.1:9090/v1/server_info): not required
• APISIX Dashboard version, if relevant: not required
• Plugin runner version, for issues related to plugin runners: not required
• LuaRocks version, for installation issues (run luarocks --version): not required