Backport of test: force IPv4 on Docker 26+ to fix Envoy int tests into release/1.16.x

[dhiaayachi]

Backport

This PR is auto-generated from hashicorp#20986 to be assessed for backporting due to the inclusion of the label backport/1.16.

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

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As of Docker Engine 26.0.0 (moby/moby#47062), IPv6 is enabled by default where supported. This causes issues for our tests attempting to resolve requests to other containers over localhost, since on Linux IPv6 will be preferred over IPv4 when available when applying the default behavior defined in RFC3484.

As a workaround, force IPv4 with a flag passed to docker run.

Testing & Reproduction steps

CI continues to pass (Docker Engine version is still <26 on runners used for CE builds).

Links

moby/moby#47062

PR Checklist

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

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Overview of commits

• a27d118