Fix #1102: fix txn_commit() for read requests
Fix #1102: fix txn_commit() for read requests

rtsisyk/tarantool,mejedi/tarantool,rtsisyk/tarantool,ocelot-inc/tarantool,ocelot-inc/tarantool,mejedi/tarantool,mejedi/tarantool,rtsisyk/tarantool,rtsisyk/tarantool,ocelot-inc/tarantool,mejedi/tarantool,ocelot-inc/tarantool