Investigate customizing netty resolver used by Azure SDK

[rjernst]

With the new version of the Azure SDK (12.11.1), the sdk switched to using Netty to internally resolve dns. The new resolver tries to look at /etc/hosts as well as /etc/resolver and /etc/resolv.conf.

We have been trying to limit how plugins are able to interact with the system. We don't want plugins reading arbitrary files from the system (see an explanation in #69464). This issue is to investigate whether we can avoid using the netty dns resolver that looks at these system configuration files.

[elasticmachine]

Pinging @elastic/es-distributed (Team:Distributed)