v2.0.4: Explicitly check for date while parsing so that datetime does not match

[dmosorast]

Description of change

While debugging a separate issue, I noticed that datetimes of the format "\/Date(1419937200000+0000)\/" as documented by Xero here were being truncated to date only.

The root of the issue was that isinstance(value, date) also matches datetime data types, so both were going down that path.

This PR makes the check explicitly for date only to avoid any conflict.

Manual QA steps

• Ran through this in a PDB session and it worked out for both date and datetime

Testing Notes

Original behavior

ipdb> value
datetime.datetime(2020, 5, 13, 14, 20, 6, 547000)
ipdb> isinstance(value, date)
True
ipdb> isinstance(value, datetime)
True
ipdb> testdt = date(1976,10,10)
ipdb> isinstance(testdt, datetime)
False
ipdb> isinstance(testdt, date)
True

New Behavior

ipdb> testdt = date(1976,10,10)
ipdb> type(testdt) is date
True
ipdb> type(testdt) is datetime
False
ipdb> testdtt = datetime(1976,10,10,1,2,3)
ipdb> type(testdtt) is datetime
True
ipdb> type(testdtt) is date
False

Risks

• Low, it's a relatively straightforward change, albeit a subtle cause.

Rollback steps

• revert this branch, bump patch version, re-release