backend: fix Peer persistent keepalive

Right now, the persistent keepalive field of the Peer CRD is always
interpretted as nanoseconds and not seconds. This causes a mismatch
between Kilo's expected behavior and the actual interval that is given
to Peers. Because the interval is interpretted as nanoseconds the value
rounds down to 0 seconds.

Signed-off-by: Lucas Servén Marín <lserven@gmail.com>

pkg/k8s/backend_test.go

@@ -511,7 +511,7 @@ func TestTranslatePeer(t *testing.T) {
 		{
 			name: "valid keepalive",
 			spec: v1alpha1.PeerSpec{
-				PersistentKeepalive: 1 * int(time.Second),
+				PersistentKeepalive: 1,
 			},
 			out: &mesh.Peer{
 				Peer: wireguard.Peer{