feat(blob-fetcher): use updated blob fetcher

[hannahhoward]

Goals

Read sharded dag indexes properly, even in the absense of location claims

Implementation

• use update blob-fetcher
• pass values to enable carpark fallback
• add two tests to verify:
  • that normal index shard fetching works in the presence of location claims
  • that in the absense of location claims it can fill in the missing values.