removed redundant comment

Signed-off-by: Vasiliy Rumyantsev <4119114+xBazilio@users.noreply.github.com>

pkg/store/bucket.go

@@ -2145,7 +2145,7 @@ func (s *BucketStore) LabelValues(ctx context.Context, req *storepb.LabelValuesR
 					}
 
 					val := labelpb.ZLabelsToPromLabels(ls.GetSeries().Labels).Get(req.Label)
-					if val != "" { // Should never be empty since we added labelName!="" matcher to the list of matchers.
+					if val != "" {
 						values[val] = struct{}{}
 					}
 				}