Backport of modified unsupported envoy version error into release/1.15.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #16518 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

• When an envoy version is out of a supported range, we now return the envoy version being used as major.minor.x to indicate that it is the minor version at most that is incompatible
• When an envoy version is in the list of unsupported envoy versions we return back the envoy version in the error message as major.minor.patch as now the exact version matters.

Note: Currently we do not have any envoy versions in the list of unsupported versions but we can support this in the future should the need arise to invalidate a particular major, minor or patch version

Testing & Reproduction steps

Verified error message with envoy out of bounds:

dc1svc2    | Envoy version 1.18.x is not supported. If there is a reason you need to use this version of envoy use the ignore-envoy-compatibility flag. Using an unsupported version of Envoy is not recommended and your experience may vary. For more information on compatibility see https://developer.hashicorp.com/consul/docs/connect/proxies/envoy#envoy-and-consul-client-agent

Verified error message with envoy in unsupported list:

dc1svc2    | Envoy version 1.18.3 is not supported. If there is a reason you need to use this version of envoy use the ignore-envoy-compatibility flag. Using an unsupported version of Envoy is not recommended and your experience may vary. For more information on compatibility see https://developer.hashicorp.com/consul/docs/connect/proxies/envoy#envoy-and-consul-client-agent

Links

PR Checklist

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

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Overview of commits

• f7636be

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

Auto approved Consul Bot automated PR