Removed redundant tests in test_extract_trunc.
Removed redundant tests in test_extract_trunc.

tzinfo is ignored for DateFields and TimeFields, and it's already
covered by DateFunctionTests.test_trunc_func().

adamchainz/django,MarkusH/django,freakboy3742/django,django/django,elena/django,monetate/django,apollo13/django,solarissmoke/django,solarissmoke/django,django/django,django/django,freakboy3742/django,wkschwartz/django,atul-bhouraskar/django,adamchainz/django,koordinates/django,rsalmaso/django,dsanders11/django,monetate/django,django/django,manhhomienbienthuy/django,MarkusH/django,felixxm/django,ghickman/django,wkschwartz/django,adamchainz/django,ghickman/django,auvipy/django,shaib/django,monetate/django,felixxm/django,apollo13/django,takis/django,elena/django,pauloxnet/django,elena/django,takis/django,blighj/django,felixxm/django,koordinates/django,pauloxnet/django,takis/django,dsanders11/django,ghickman/django,wkschwartz/django,auvipy/django,rsalmaso/django,shaib/django,monetate/django,adamchainz/django,MarkusH/django,shaib/django,wkschwartz/django,felixxm/django,freakboy3742/django,koordinates/django,blighj/django,takis/django,auvipy/django,blighj/django,apollo13/django,rsalmaso/django,pauloxnet/django,atul-bhouraskar/django,atul-bhouraskar/django,ghickman/django,koordinates/django,blighj/django,pauloxnet/django,shaib/django,dsanders11/django,manhhomienbienthuy/django,atul-bhouraskar/django,rsalmaso/django,elena/django,dsanders11/django,manhhomienbienthuy/django,solarissmoke/django,manhhomienbienthuy/django,solarissmoke/django,auvipy/django,MarkusH/django,apollo13/django