Merge pull request #88531 from claudiubelu/tests/configurable-private-image-pull

tests: Adds configurable docker conf for test

hack/ginkgo-e2e.sh

@@ -169,6 +169,7 @@ export PATH
   --network="${KUBE_GCE_NETWORK:-${KUBE_GKE_NETWORK:-e2e}}" \
   --node-tag="${NODE_TAG:-}" \
   --master-tag="${MASTER_TAG:-}" \
+  --docker-config-file="${DOCKER_CONFIG_FILE:-}" \
   --dns-domain="${KUBE_DNS_DOMAIN:-cluster.local}" \
   --ginkgo.slowSpecThreshold="${GINKGO_SLOW_SPEC_THRESHOLD:-300}" \
   ${KUBE_CONTAINER_RUNTIME:+"--container-runtime=${KUBE_CONTAINER_RUNTIME}"} \