Add parent controller functionality to fetchCidWithRace

[AmeanAsad]

Description

• Currently, fetchCid is able to accept an external controller to use for making requests. That allows the client making the request to abort it on its own terms (custom timeout, data size limit, etc.)
• fetchCidWithRace doesn't currently support that. It adds a layer of complexity because it races multiple nodes, and therefore requires multiple controllers.

Rough Approach:

• the ideal approach here is to have a hierarchy over controllers. The client is able to pass a controller that kills all the controllers being used in the fetches but we should still have the ability to abort each request indepedently using its own controller.