Deprecation Warning in serialization.py

[VMRuiz]

The following line of code is triggering a deprecation warning:

python-scrapinghub/scrapinghub/hubstorage/serialization.py

Line 5 in b3b2e1d

EPOCH = datetime.utcfromtimestamp(0)

DeprecationWarning: datetime.datetime.utcfromtimestamp() is deprecated and scheduled for removal in a future version. 
Use timezone-aware objects to represent datetimes in UTC: datetime.datetime.fromtimestamp(timestamp, datetime.UTC).

According to the message, the recommended fix is to use timezone-aware objects with datetime.datetime.fromtimestamp(timestamp, datetime.UTC).