Only run TestDockerFlags with docker container runtime

This test is failing for contaienrd tests, but it doesn't make sense to run it with anything but docker.
Adding in a skip.

test/integration/docker_test.go

@@ -30,6 +30,9 @@ func TestDockerFlags(t *testing.T) {
 	if NoneDriver() {
 		t.Skip("skipping: none driver does not support ssh or bundle docker")
 	}
+	if ContainerRuntime() != "docker" {
+		t.Skipf("skipping: only runs with docker container runtime, currently testing %s", ContainerRuntime())
+	}
 	MaybeParallel(t)
 
 	profile := UniqueProfileName("docker-flags")