Relax pip dependency versions constraints for python-dateutil

[dchichkov]

Description of the problem:
ERROR: dvc 0.93.0 has requirement python-dateutil <2.8.1 ,>=2.1, but you'll have python-dateutil 2.8.1 which is incompatible.

It'd be good to remove or relax upper constraints on python-dateutil, to include 2.8.1 and 2.8.2. Is there a good reason why these are not included, or something is broken after 2.8.1 ?

[efiop]

Hi @dchichkov !

Mind submitting a PR to remove it? https://github.com/iterative/dvc/blob/master/setup.py#L50 It is an old sync requirement that is probably no longer needed. We'll see in the PR CI tests.