[#8] cli: Set flag mode required for control shards set-mode

Signed-off-by: Anton Nikiforov <an.nikiforov@yadro.com>

CHANGELOG.md

@@ -18,6 +18,7 @@ Changelog for FrostFS Node
 - Fetching blobovnicza objects that not found in write-cache (#2206)
 - Do not search for the small objects in FSTree (#2206)
 - Correct status error for expired session token (#2207)
+- Set flag `mode` required for `frostfs-cli control shards set-mode` (#8)
 
 ### Removed
 ### Updated

cmd/frostfs-cli/modules/control/shards_set_mode.go

@@ -93,6 +93,7 @@ func initControlSetShardModeCmd() {
 	flags.String(shardModeFlag, "",
 		fmt.Sprintf("New shard mode (%s)", strings.Join(modes, ", ")),
 	)
+	_ = setShardModeCmd.MarkFlagRequired(shardModeFlag)
 	flags.Bool(shardClearErrorsFlag, false, "Set shard error count to 0")
 
 	setShardModeCmd.MarkFlagsMutuallyExclusive(shardIDFlag, shardAllFlag)