unmute olap-kqp-mvcc tests (#9655)

.github/config/muted_ya.txt

@@ -25,8 +25,6 @@ ydb/core/kqp/ut/service [*/*]*
 ydb/core/kqp/ut/service KqpQueryService.ExecuteQueryPgTableSelect
 ydb/core/kqp/ut/service KqpQueryService.QueryOnClosedSession
 ydb/core/kqp/ut/service KqpService.CloseSessionsWithLoad
-ydb/core/kqp/ut/tx KqpSinkMvcc.OlapNamedStatement
-ydb/core/kqp/ut/tx KqpSinkMvcc.OlapMultiSinks
 ydb/core/persqueue/ut [*/*]*
 ydb/core/persqueue/ut TPQTest.*DirectRead*
 ydb/core/persqueue/ut/ut_with_sdk [*/*]*