Fixing integration test sp_guarulhos

[rqclima]

sp_guarulhos integration test was failing, it seems that the available gazettes in that month had changed from 17 to 16.

[rennerocha]

For most of the spiders that I saw the contract failing, the solution was to fix just the contract, not the spider code. I don't see that this kind of test is useful and I'd suggest that we stop using contracts this way and maybe thinking in different ways of monitoring the results.

[rqclima]

It would be really nice if we can find some other way of monitoring the sanity of these spiders. These tests are really fragile (the spiders are, as the sites can change anytime without notice). And some of the tests look for different data every day, making them even more fragile.

Anyway, it at least tests an important part of the code. And right now it's failing, so I just thought of getting it working again, and then we can think of improving it.

[rennerocha]

Contracts on spiders were removed in 3eaeba4 . Discussion related: #44
As we are not using contracts, this PR is not needed anymore.