move gotd fork into repo. (#111)

- update to latest telegram layer
- remove some references to fields in tg.Entities that don't exist in
the schema
- originally added here:
https://github.com/beeper/td/commit/820929062a2ba0104397bc01235ab58a9cff780e
  - referenced here
-
https://github.com/mautrix/telegramgo/commit/124f0967ed195b5a380c9bd02e170ada9710dde3
-
https://github.com/mautrix/telegramgo/commit/4205047aab2e0639217148b5d125bfaab668bd8e

pkg/gotd/session/storage_mem_test.go

@@ -0,0 +1,43 @@
+package session
+
+import (
+	"bytes"
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestStorageMemory(t *testing.T) {
+	t.Run("Storage", testStorage(&StorageMemory{}))
+}
+
+func TestStorageMemory_Dump(t *testing.T) {
+	a := require.New(t)
+	ctx := context.Background()
+	data := bytes.Repeat([]byte{'a'}, 256)
+
+	a.ErrorIs((*StorageMemory)(nil).Dump(nil), ErrNotFound)
+
+	s := StorageMemory{}
+	a.ErrorIs(s.Dump(nil), ErrNotFound)
+
+	a.NoError(s.StoreSession(ctx, data))
+	out := bytes.Buffer{}
+	a.NoError(s.Dump(&out))
+	a.Equal(data, out.Bytes())
+}
+
+func TestStorageMemory_Clone(t *testing.T) {
+	a := require.New(t)
+	ctx := context.Background()
+	data := bytes.Repeat([]byte{'a'}, 256)
+	tmp := data[0]
+
+	s := StorageMemory{}
+	a.NoError(s.StoreSession(ctx, data))
+
+	s2 := s.Clone()
+	s.data[0]--
+	a.Equal(tmp, s2.data[0])
+}