Conformance test are a subset of the e2e test Kubernetes test.
The e2e tests are based on Ginkgo https://onsi.github.io/ginkgo/ and live in the Kubernetes repository https://github.com/kubernetes/kubernetes/tree/master/test/e2e.
There is no guarantee of compatibility for the e2e binaries, hence the e2e binary version MUST match your kubernetes cluster version.