feat: add updateOperator

[eordano]

No description provided.

[cazala]

looks like the linter is complaining ☝️

[nicosantangelo]

Two things:

• To add a new validation to the sanity check, you should go to https://github.com/decentraland/marketplace/blob/master/sanity/doctors/ParcelDoctor.js#L45. The ParcelDiagnosis will take care of the fixing part in this case, so no code needed there, if you want, you could add an update removing update_operator here, but I think that if the blockchain events are re-fetched it should work fine.
• The tests are failing just because we need to add update_operator to the expected object

Other than that, I tested and it seems to work fine :D!

[cazala]

@eordano looking good but needs rebase