Fix error in test comment

The test is ensuring config reload fails when trying to change cluster
host.

server/configs/reload/reload_unsupported.conf

@@ -3,5 +3,7 @@
 # logging options
 debug:   false
 trace:   true
-logtime: true # logtime not supported on config reload
+logtime: true
 log_file: "/tmp/gnatsd.log"
+
+# Removes cluster host, which is unsupported.

server/reload_test.go

@@ -71,7 +71,7 @@ func TestConfigReloadUnsupported(t *testing.T) {
 		t.Fatalf("Error creating symlink: %v (ensure you have privileges)", err)
 	}
 
-	// This should fail because `debug` cannot be changed.
+	// This should fail because `cluster` host cannot be changed.
 	if err := server.Reload(); err == nil {
 		t.Fatal("Expected Reload to return an error")
 	}