[client-v2] While POJO Serialization and saving LocalDateTime to DateTime64 no Timezone is passed

[chernser]

Description

There seems a problem with writing datetime values in the new client. One of cases is when LocalDateTime is written thru serializers to DateTime64 values.

To fix the issue we need to test:

1. client and server in different timezones
2. saving LocalDateTime
3. saving Instant
4. saving ZonedDateTime
5. saving Date
6. ... other date time classes

Most important to verify is how timezone is applied when client and server have different ones.