Tests: Use UTC-based utcnow().date() instead of local date.today()

`datetime.date.today()` returns the current local date. In order to
reduce test flakyness when comparing UTC-based datetimes with localtime-
based variants, `datetime.utcnow().date()` is a better choice.

src/crate/client/sqlalchemy/doctests/itests.txt

@@ -105,7 +105,7 @@ aren't set when the row is inserted as there is no default method::
 
 The datetime and date can be set using a update statement::
 
-    >>> location.nullable_date = datetime.today()
+    >>> location.nullable_date = datetime.utcnow().date()
     >>> location.nullable_datetime = datetime.utcnow()
     >>> session.flush()
 

src/crate/client/tests.py

@@ -27,7 +27,7 @@
 import unittest
 import doctest
 from pprint import pprint
-from datetime import datetime, date
+from datetime import datetime
 from http.server import HTTPServer, BaseHTTPRequestHandler
 import ssl
 import time
@@ -213,7 +213,7 @@ class Location(Base):
         __tablename__ = 'locations'
         name = sa.Column(sa.String, primary_key=True)
         kind = sa.Column(sa.String)
-        date = sa.Column(sa.Date, default=date.today)
+        date = sa.Column(sa.Date, default=lambda: datetime.utcnow().date())
         datetime_tz = sa.Column(sa.DateTime, default=datetime.utcnow)
         datetime_notz = sa.Column(sa.DateTime, default=datetime.utcnow)
         nullable_datetime = sa.Column(sa.DateTime)