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: 6a28c0a
Author: Nikita Skrynnik
Date: 2024-04-05 15:54:38 +0700
Message:
  - Update gRPC health probe to fix CVEs (#670)
Signed-off-by: NSMBot <nsmbot@networkservicmesh.io>

apps/nsmgr/nsmgr.yaml

@@ -17,7 +17,7 @@ spec:
     spec:
       serviceAccount: nsmgr-sa
       containers:
-        - image: ghcr.io/networkservicemesh/ci/cmd-nsmgr:f44b6a0
+        - image: ghcr.io/networkservicemesh/ci/cmd-nsmgr:6a28c0a
           imagePullPolicy: IfNotPresent
           name: nsmgr
           ports: