[#1696] qos: Fix internal tag adjust

If request has no tag, but request's public key is netmap node's key or
one of allowed internal tag keys from config, then request must use
internal IO tag.

Change-Id: Iff93b626941a81b088d8999b3f2947f9501dcdf8
Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/util/testing/netmap_source.go

@@ -0,0 +1,36 @@
+package testing
+
+import (
+	"context"
+	"errors"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
+)
+
+var (
+	errInvalidDiff    = errors.New("invalid diff")
+	errNetmapNotFound = errors.New("netmap not found")
+)
+
+type TestNetmapSource struct {
+	Netmaps      map[uint64]*netmap.NetMap
+	CurrentEpoch uint64
+}
+
+func (s *TestNetmapSource) GetNetMap(ctx context.Context, diff uint64) (*netmap.NetMap, error) {
+	if diff >= s.CurrentEpoch {
+		return nil, errInvalidDiff
+	}
+	return s.GetNetMapByEpoch(ctx, s.CurrentEpoch-diff)
+}
+
+func (s *TestNetmapSource) GetNetMapByEpoch(_ context.Context, epoch uint64) (*netmap.NetMap, error) {
+	if nm, found := s.Netmaps[epoch]; found {
+		return nm, nil
+	}
+	return nil, errNetmapNotFound
+}
+
+func (s *TestNetmapSource) Epoch(context.Context) (uint64, error) {
+	return s.CurrentEpoch, nil
+}