Backport of fix: add tls config to unix socket when https is used into release/1.15.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #16301 to be assessed for backporting due to the inclusion of the label backport/1.15.

The below text is copied from the body of the original PR.

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Description

Add tls config to unix socket when https is used

Testing & Reproduction steps

Manually tested with the following agent config

"addresses": {
        "grpc_tls" : "unix://consul/consul_grpc.sock",
        "http" : "unix://consul/consul_http.sock",
        "https" : "unix://consul/consul_https.sock"
    },

export CONSUL_HTTP_ADDR=unix://consul/consul_https.sock
CONSUL_HTTP_SSL=true consul connect 

Links

fix #16252

PR Checklist

• updated test coverage
• external facing docs updated
• not a security concern

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Overview of commits

• 49f7423 - d5408c8

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR