Fixes failing spec caused by imprecise date comparison on slow CI server...

I noticed a failing spec on travis a few times now (e.g.: https://travis-ci.org/magiclabs/alchemy_cms/jobs/37617484). I changed the way of the date comparison in the spec to make sure it also passes on slow CI servers.
This is exactly for slow CI servers, if you remove the `be_within(1.second)`, then the time has to be exactly like `2.weeks.ago`. If you keep it like it was, the time difference can be `1.second`

So your fix isn't a fix, you are actually removing the fix and introduced a regression.