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

…d-nsmgr@main

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

Commit: 5a3e43b
Author: Авраменко Михаил
Date: 2021-10-28 13:04:44 +0700
Message:
  - removed usage of old methods from manager (#394)
Signed-off-by: NSMBot <nsmbot@networkservicmesh.io>

apps/nsmgr/nsmgr.yaml

@@ -16,7 +16,7 @@ spec:
         "spiffe.io/spiffe-id": "true"
     spec:
       containers:
-        - image: ghcr.io/networkservicemesh/ci/cmd-nsmgr:e0b308a
+        - image: ghcr.io/networkservicemesh/ci/cmd-nsmgr:5a3e43b
           imagePullPolicy: IfNotPresent
           name: nsmgr
           ports: