VOL-2861 replace uint64 kafka interadapter timestamps with timestamp proto

Change-Id: I7b0fe854ff7c91984237a111789603129151dba3
diff --git a/cmd/openolt-adapter/main_test.go b/cmd/openolt-adapter/main_test.go
index cffc9fc..5246348 100644
--- a/cmd/openolt-adapter/main_test.go
+++ b/cmd/openolt-adapter/main_test.go
@@ -21,6 +21,7 @@
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 	"testing"
+	"time"
 
 	"github.com/opencord/voltha-lib-go/v3/pkg/kafka"
 	"github.com/opencord/voltha-openolt-adapter/internal/pkg/config"
@@ -224,6 +225,6 @@
 	return nil
 }
 
-func (kc *mockKafkaClient) SubscribeForMetadata(func(fromTopic string, timestamp int64)) {
+func (kc *mockKafkaClient) SubscribeForMetadata(func(fromTopic string, timestamp time.Time)) {
 	return
 }