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: 86644b9
Author: Vladimir Popov
Date: 2021-08-11 21:15:24 +0700
Message:
  - Fix resetting credentials (#357)
Signed-off-by: NSMBot <nsmbot@networkservicmesh.io>

apps/nsmgr/nsmgr.yaml

@@ -15,7 +15,7 @@ spec:
         app: nsmgr
     spec:
       containers:
-        - image: ghcr.io/networkservicemesh/ci/cmd-nsmgr:12fc791
+        - image: ghcr.io/networkservicemesh/ci/cmd-nsmgr:86644b9
           imagePullPolicy: IfNotPresent
           name: nsmgr
           ports: