metrics: fix neofs_node_engine_list_objects_time_bucket

The metric was called in a function that was not called anywhere because there
is a similar function that is being used. Now the metric is called on the used
function.

Fix #3108.

Signed-off-by: Andrey Butusov <[email protected]>

Author: End-rey

CHANGELOG.md

@@ -19,6 +19,7 @@ Changelog for NeoFS Node
 - The parent of the split object is not removed from the metabase (#3089)
 - A split expired object is not deleted after the lock is removed or expired (#3089)
 - `neofs_node_engine_list_containers_time_bucket` and `neofs_node_engine_exists_time_bucket` metrics (#3014)
+- `neofs_node_engine_list_objects_time_bucket` metric (#3120)
 
 ### Changed
 - Number of cuncurrenly handled notifications from the chain was increased from 10 to 300 for IR (#3068)

pkg/local_object_storage/engine/list.go

@@ -28,6 +28,10 @@ type Cursor struct {
 // Returns ErrEndOfListing if there are no more objects to return or count
 // parameter set to zero.
 func (e *StorageEngine) ListWithCursor(count uint32, cursor *Cursor) ([]objectcore.AddressWithType, *Cursor, error) {
+	if e.metrics != nil {
+		defer elapsed(e.metrics.AddListObjectsDuration)()
+	}
+
 	result := make([]objectcore.AddressWithType, 0, count)
 
 	// 1. Get available shards and sort them.