Currently Elasticsearch template uses `HTTP_AGENT` which is executed by Zabbix Server

https://git.zabbix.com/projects/ZBX/repos/zabbix/browse/templates/app/elasticsearch_http?at=release/7.0

But it can use `web.page.get`. Then it can be used with active and passive agents.

I am attaching examples that I modified from a Zabbix 6 installation (although exported from Zabbix7). But perhaps my example does not have the latest changes to the template. So one must adapt from the latest version. (I am just not sure how to deal with UUIDs in that case)

As an added advantage, the active checks can access the cluster node from `localhost`. This way, this template can have both active and passive versions and it won't require additional ports to open for monitoring etc. Any zabbix agent can be used to monitor the cluster.

I believe this change would benefit the Zabbix/Elasticsearch users? or perhaps provide 3 different templates? HTTP_AGENT, passive and active?