output data to zabbix with https schema

[jiaxuanzhou]

Problem

currently output data to zabbix without any encrypted way, but in product environment, the zabbix server often visited by https schema, so can we support https schema in configurations ？
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Steps to replicate

Provide example config and message

Expected Behavior

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Your environment

• OS version
• paste result of fluentd --version or td-agent --version
• plugin version
  • paste boot log of fluentd or td-agent
  • paste result of fluent-gem list, td-agent-gem list or your Gemfile.lock