Running tests in UTC+2 timezone makes some of the tests fail because the
mocked time in the future is actually in the past, as UTC is used as the
new reference point. Adjust the tests to mock also the time when the
first execution of function happens.
Instances where the second execution happened "immediately" were mocked
to happen 1ms later. The 1ms delta is also needed to be added when
mocking time 1h in the future, otherwise it will be throttled too.