Update go.mod and go.sum to latest version from networkservicemesh/cm…

…d-forwarder-vpp@main

PR link: https://github.com/networkservicemesh/cmd-forwarder-vpp/pull/

Commit: d531e5d
Author: zolug
Date: 2021-10-07 16:23:45 +0200
Message:
  - Make vxlan port configurable (#341) (#352)
networkservicemesh/sdk-vpp commit message:
Make vxlan port configurable (see networkservicemesh/sdk-vpp#394)

networkservicemesh/sdk commit message:
Make vxlan port configurable (see networkservicemesh/sdk#1091)

Signed-off-by: NSMBot <nsmbot@networkservicmesh.io>

apps/forwarder-vpp/forwarder.yaml

@@ -18,7 +18,7 @@ spec:
       hostNetwork: true
       dnsPolicy: ClusterFirstWithHostNet
       containers:
-        - image: ghcr.io/networkservicemesh/ci/cmd-forwarder-vpp:0f11313
+        - image: ghcr.io/networkservicemesh/ci/cmd-forwarder-vpp:d531e5d
           imagePullPolicy: IfNotPresent
           name: forwarder-vpp
           securityContext: