valid tests failing on slower CI instances

[radiovisual]

This valid test:

test('records total seconds', async t => {
    // ...
    await wait(3);
    await timecard.clockout();

    t.is(timecard.totalSeconds, 3);
});

...periodically fails on travis if the process takes too long, and the "waiting" of 3 seconds actually turns into 4 or 5 seconds, so the test needs to be a bit more lenient, like looking for a minimum of 3:

t.true(timecard.totalSeconds >= 3);