Backport of test: add a v2 container integration test of xRoute splits into release/1.17.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #19570 to be assessed for backporting due to the inclusion of the label backport/1.17.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
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The person who merged in the original PR is:
@rboyer
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

merge conflict error: POST https://api.github.com/repos/hashicorp/consul/merges: 409 Merge conflict []

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

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Description

This adds a deployer-based integration test verifying that a 90/10 traffic split works for: HTTPRoute, GRPCRoute, and TCPRoute.

Ordinarily we would use fortio to verify the destinations reached during the test, but there wasn't a good way to exploit its gRPC ping service to unearth the original app identity, so for now I wrote a quick server to reply in a protocol-specific way with a user-defined name that works for http, http2, grpc, and plain tcp: https://github.com/rboyer/blankspace

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Overview of commits

• 469a7a8 - e17ccae - 460fdd6 - 36f339a - e763a08 - 28b8c95 - d808c18 - 38ed20b - c1e754b - f8a40d8 - 2e81c82 - 399517b - 0f8736f - 588545d - 22a3e0f

[hashicorp-cla]

All committers have signed the CLA.

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

Auto approved Consul Bot automated PR