storage,kv: read error injection roachtest

Pebble has randomized error injection within some unit tests that ensure errors encountered in read paths are surfaced through the top-level Iterator. However, I don't believe we have much end-to-end testing of error injection within Cockroach. We could use Pebble's vfs error injection within a roachtest to ensure that errors are handled appropriately end-to-end.

We also need end-to-end testing of write errors, but that's more challenging and shouldn't hold up the read testing.

Jira issue: CRDB-35395