Backport of NET-6821 Disable Terminating Gateway Auto Host Header Rewrite into release/1.18.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #20802 to be assessed for backporting due to the inclusion of the label backport/1.18.

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

---

Description

• Exposing configuration to allow users of the terminating gateway to turn off host header rewrites at the service level

Testing & Reproduction steps

• build local consul
• apply the following terminating gateway

Kind = "terminating-gateway"
Name = "test-gateway"
Services = [
 {
   Name = "default-behavior"
 },
 {
   Name = "default-behavior"
   DisableAutoHostRewrite = true
 }
]

Observe the generated XDS and note that the default behavior is to auto host rewrite, but not when DisableAutoHostRewrite is set to true.

Links

PR Checklist

• [ X ] updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 3790378 - bad1b43 - 542c9d8 - 7eeb594 - 11e4a74 - 5bdf8b0

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

Auto approved Consul Bot automated PR

[sarahalsmiller]

Suggested change

	'When set to true, Terminating Gateway will not modify the incoming requests host header for this service.',
	'When set to true, Terminating Gateway will not modify the incoming requests host header for this service. Available in Consul v1.18.1 or later.',

[david-yu]

@sarahalsmiller Looks like this still is outstanding as a backport for 1.18.x