Fix HTTP 504 errors in the pipeline

We tend to get some HTTP 504 error codes in the pipeline. This is probably because we're hitting one particular IPFS gateway a lot with each pipeline run.

One solution would be to use a few different gateways and spread the load. This would also allow us to hit another gateway in case we experience a problem from one of them, and thus checking if it's a gateway problem, or problem with the actual content.