Oci worker binary documentation and add missing constructor arg in runc_test

Signed-off-by: Nikhil Pandeti <nikhil.pandeti@utexas.edu>

docs/buildkitd.toml.md

@@ -46,7 +46,9 @@ insecure-entitlements = [ "network.host", "security.insecure" ]
   noProcessSandbox = false
   gc = true
   gckeepstorage = 9000
-  binary = "" # OCI worker binary name, default binary is buildkit-runc
+  # alternate OCI worker binary name(example 'crun'), by default either 
+  # buildkit-runc or runc binary is used
+  binary = ""
   [worker.oci.labels]
     "foo" = "bar"
 

worker/runc/runc_test.go

@@ -40,7 +40,7 @@ func newWorkerOpt(t *testing.T, processMode oci.ProcessMode) (base.WorkerOpt, fu
 		},
 	}
 	rootless := false
-	workerOpt, err := NewWorkerOpt(tmpdir, snFactory, rootless, processMode, nil, nil, netproviders.Opt{Mode: "host"}, nil)
+	workerOpt, err := NewWorkerOpt(tmpdir, snFactory, rootless, processMode, nil, nil, netproviders.Opt{Mode: "host"}, nil, "")
 	require.NoError(t, err)
 
 	return workerOpt, cleanup