[MM-29217] Remove Posts.ParentId (#17923)

services/cache/lru_test.go

@@ -139,7 +139,6 @@ func TestLRUMarshalUnMarshal(t *testing.T) {
 		UserId:        "UserId",
 		ChannelId:     "ChannelId",
 		RootId:        "RootId",
-		ParentId:      "ParentId",
 		OriginalId:    "OriginalId",
 		Message:       "OriginalId",
 		MessageSource: "MessageSource",
@@ -487,7 +486,6 @@ func BenchmarkLRU(b *testing.B) {
 		UserId:        "UserId",
 		ChannelId:     "ChannelId",
 		RootId:        "RootId",
-		ParentId:      "ParentId",
 		OriginalId:    "OriginalId",
 		Message:       "OriginalId",
 		MessageSource: "MessageSource",