Add v2 version to go module name

Replace all elements from `v2` to root directory.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

refs/test/generate.go

@@ -0,0 +1,105 @@
+package refstest
+
+import (
+	"github.com/nspcc-dev/neofs-api-go/v2/refs"
+)
+
+func GenerateVersion(empty bool) *refs.Version {
+	m := new(refs.Version)
+
+	if !empty {
+		m.SetMajor(2)
+		m.SetMinor(1)
+	}
+
+	return m
+}
+
+func GenerateOwnerID(empty bool) *refs.OwnerID {
+	m := new(refs.OwnerID)
+
+	if !empty {
+		m.SetValue([]byte{1, 2, 3})
+	}
+
+	return m
+}
+
+func GenerateAddress(empty bool) *refs.Address {
+	m := new(refs.Address)
+
+	if !empty {
+		m.SetObjectID(GenerateObjectID(false))
+		m.SetContainerID(GenerateContainerID(false))
+	}
+
+	return m
+}
+
+func GenerateObjectID(empty bool) *refs.ObjectID {
+	m := new(refs.ObjectID)
+
+	if !empty {
+		m.SetValue([]byte{1, 2, 3})
+	}
+
+	return m
+}
+
+func GenerateObjectIDs(empty bool) []*refs.ObjectID {
+	var ids []*refs.ObjectID
+
+	if !empty {
+		ids = append(ids,
+			GenerateObjectID(false),
+			GenerateObjectID(false),
+		)
+	}
+
+	return ids
+}
+
+func GenerateContainerID(empty bool) *refs.ContainerID {
+	m := new(refs.ContainerID)
+
+	if !empty {
+		m.SetValue([]byte{1, 2, 3})
+	}
+
+	return m
+}
+
+func GenerateContainerIDs(empty bool) []*refs.ContainerID {
+	var res []*refs.ContainerID
+
+	if !empty {
+		res = append(res,
+			GenerateContainerID(false),
+			GenerateContainerID(false),
+		)
+	}
+
+	return res
+}
+
+func GenerateSignature(empty bool) *refs.Signature {
+	m := new(refs.Signature)
+
+	if !empty {
+		m.SetKey([]byte{1})
+		m.SetSign([]byte{2})
+	}
+
+	return m
+}
+
+func GenerateChecksum(empty bool) *refs.Checksum {
+	m := new(refs.Checksum)
+
+	if !empty {
+		m.SetType(1)
+		m.SetSum([]byte{1, 2, 3})
+	}
+
+	return m
+}