DefaultTokenProviderTest mocked/asserted the wrong method

[ChristophWurst]

It's 'getRemember' instead of 'getRememberMe', hence some warnings
were generated by phpunit.

Partially fixes

There were 3 warnings:
1) Test\Authentication\Token\DefaultTokenProviderTest::testRenewSessionTokenWithoutPassword
Trying to configure method "getRememberMe" which cannot be configured because it does not exist, has not been specified, is final, or is static
2) Test\Authentication\Token\DefaultTokenProviderTest::testRenewSessionTokenWithPassword
Trying to configure method "getRememberMe" which cannot be configured because it does not exist, has not been specified, is final, or is static
3) OCA\Provisioning_API\Tests\Controller\UsersControllerTest::testGetCurrentUserLoggedIn
PHPUnit_Framework_TestCase::getMock() is deprecated, use PHPUnit_Framework_TestCase::createMock() or PHPUnit_Framework_TestCase::getMockBuilder() instead

Seen in https://drone.nextcloud.com/nextcloud/server/5553/3

[mention-bot]

@ChristophWurst, thanks for your PR! By analyzing the history of the files in this pull request, we identified @LukasReschke and @rullzer to be potential reviewers.

[rullzer]

And the tests still passes 🙈