Add support for time and duration types

[lovromazgon]

Description

Adds support for generating actual time.Time objects and time.Duration values.

Depends on https://github.com/ConduitIO/conduit-commons/pull/84 to work end-to-end.

Quick checks:

• [X] I have followed the Code Guidelines.
• [X] There is no other pull request for the same update/change.
• [X] I have written unit tests.
• [X] I have made sure that the PR is of reasonable size and can be easily reviewed.