feat(blobs): Emulated CL end point for e2e tests

[Maddiaa0]

Overview

Part of larger meta issue #9101 (comment)

See engineering designs document: AztecProtocol/engineering-designs#41

We do not want to run an entire execution client / consensus layer client for our full end to end tests, instead we can run a service the emulates the response from the get blob side cars consensus layer http endpoint