removed date that is not well defined from tests

.travis.yml

@@ -44,7 +44,6 @@ install:
 # core framework:
   - travis_retry composer install --prefer-dist --no-interaction
   - tests/unit/data/travis/mongodb-setup.sh
-# TODO: APC currently fails composer. https://github.com/composer/composer/issues/3405
   - tests/unit/data/travis/apc-setup.sh
   - tests/unit/data/travis/memcache-setup.sh
   - tests/unit/data/travis/cubrid-setup.sh

tests/unit/framework/i18n/FormatterDateTest.php

@@ -198,7 +198,6 @@ class FormatterDateTest extends TestCase
 
         $this->assertSame('12-08-1922', $this->formatter->asDate('1922-08-12', 'dd-MM-yyyy'));
         $this->assertSame('14-01-1732', $this->formatter->asDate('1732-01-14', 'dd-MM-yyyy'));
-        $this->assertSame('01-01-0000', $this->formatter->asDate('0000-01-01', 'dd-MM-yyyy'));
     }
 
     public function testIntlDateRangeHigh()