multi: use the "errors" package everywhere

Replace all usages of the "github.com/go-errors/errors" and
"github.com/pkg/errors" packages with the standard lib's "errors"
package. This ensures that error wrapping and `errors.Is` checks will
work as expected.

channeldb/migration_01_to_11/meta_test.go

@@ -1,9 +1,9 @@
 package migration_01_to_11
 
 import (
+	"fmt"
 	"testing"
 
-	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lnd/kvdb"
 )
 
@@ -33,7 +33,7 @@ func applyMigration(t *testing.T, beforeMigration, afterMigration func(d *DB),
 
 	defer func() {
 		if r := recover(); r != nil {
-			err = errors.New(r)
+			err = fmt.Errorf("%v", r)
 		}
 
 		if err == nil && shouldFail {

channeldb/migration_01_to_11/migrations_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"crypto/sha256"
 	"encoding/binary"
+	"errors"
 	"fmt"
 	"math/rand"
 	"reflect"
@@ -12,7 +13,6 @@ import (
 
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/davecgh/go-spew/spew"
-	"github.com/go-errors/errors"
 	lnwire "github.com/lightningnetwork/lnd/channeldb/migration/lnwire21"
 	"github.com/lightningnetwork/lnd/kvdb"
 	"github.com/lightningnetwork/lnd/lntypes"