`IpVersions/ProxyFilterIntegrationTest.ParallelRequestsWithFakeResolver` is very flakey (ASAN)

[phlax]

[ RUN      ] IpVersions/ProxyFilterIntegrationTest.ParallelRequestsWithFakeResolver/IPv6
test/extensions/filters/http/dynamic_forward_proxy/proxy_filter_integration_test.cc:718: Failure
Expected equality of these values:
  "200"
    Which is: 0x55f5e5c71280
  response2->headers().getStatusValue()
    Which is: "503"
Stack trace:
  0x55f5e9a58d5d: Envoy::(anonymous namespace)::ProxyFilterIntegrationTest_ParallelRequestsWithFakeResolver_Test::TestBody()
  0x55f5f4b72045: testing::internal::HandleExceptionsInMethodIfSupported<>()
  0x55f5f4b249d4: testing::Test::Run()
  0x55f5f4b26d38: testing::TestInfo::Run()
... Google Test internal frames ...

https://github.com/envoyproxy/envoy/actions/runs/24453983189/job/71449741267#step:19:34090

easily reproducible

INFO: Analyzed target //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (18 packages loaded, 118 targets configured).
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 30 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_30_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 318 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_318_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 324 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_324_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 339 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_339_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 516 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_516_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 518 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_518_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 633 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_633_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 698 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_698_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 726 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_726_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 641 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_641_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 784 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_784_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 792 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_792_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 802 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_802_of_1000/test.log)
FAIL: //test/extensions/filters/http/dynamic_forward_proxy:legacy_proxy_filter_integration_test (run 972 of 1000) (see /build/bazel_root/base/execroot/envoy/bazel-out/k8-fastbuild/testlogs/test/extensions/filters/http/dynamic_forward_proxy/legacy_proxy_filter_integration_test/run_972_of_1000/test.log)

[phlax]

cc @agrawroh

[phlax]

deflake run

https://github.com/envoyproxy/envoy/actions/runs/24529068277/job/71707199493#step:19:1258