[ASENG-835] Add puller package for s3

[edznux-dd]

WIP / Discussion

PoC of a gRPC API for a remote ingestor. This is one possible solution for pulling the data from an s3 bucket that was stored previously.

This PR includes 3 blocks:

• A Puller: pulls the data from a remote source, in our case a generic implementation of a blob storage (e.g: s3)
• An API: allows users and automated system to execute command from that "ingestor"
• A notifier: allows the API to notify user and system of processing completion. This can be done via a queuing system, webhooks or something else.

Notes:

• Not a huge fan of the "ingestor" name, we probably need to convey that it's a remote API that may have extended use later on?
  • I thing the API needs to be extended for it to not be a bit over engineered here.

Alternative solution:

• Should we replace the puller by simply a custom collector (e.g: blob_collector)?
  • This would need to fit the Collector interface to pull data to s3 but could simplify a few things maybe?
  • This will match the same structure as the file collector (bundled json files with all resource, per type)