vendor: update buildkit to v0.16.0-rc2

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

vendor/google.golang.org/grpc/internal/pretty/pretty.go

@@ -24,7 +24,6 @@ import (
 	"encoding/json"
 	"fmt"
 
-	"github.com/golang/protobuf/jsonpb"
 	protov1 "github.com/golang/protobuf/proto"
 	"google.golang.org/protobuf/encoding/protojson"
 	protov2 "google.golang.org/protobuf/proto"
@@ -38,15 +37,15 @@ const jsonIndent = "  "
 func ToJSON(e any) string {
 	switch ee := e.(type) {
 	case protov1.Message:
-		mm := jsonpb.Marshaler{Indent: jsonIndent}
-		ret, err := mm.MarshalToString(ee)
+		mm := protojson.MarshalOptions{Indent: jsonIndent}
+		ret, err := mm.Marshal(protov1.MessageV2(ee))
 		if err != nil {
 			// This may fail for proto.Anys, e.g. for xDS v2, LDS, the v2
 			// messages are not imported, and this will fail because the message
 			// is not found.
 			return fmt.Sprintf("%+v", ee)
 		}
-		return ret
+		return string(ret)
 	case protov2.Message:
 		mm := protojson.MarshalOptions{
 			Multiline: true,