[Go] Add concurrent-safe ipc.FileReader.RecordAt(i)

[asfimport]

Arrow IPC files are safe to load concurrently. The implementation of ipc.FileReader.Record(i) is not safe due to stashing the current record internally. This adds a backward-compatible function RecordAt that behaves like ReadAt.

Reporter: Francois Saint-Jacques / @fsaintjacques
Assignee: Francois Saint-Jacques / @fsaintjacques

PRs and other links:

• GitHub Pull Request #9584

_{Note: This issue was originally created as ARROW-11794. Please see the migration documentation for further details.}

[asfimport]

Neal Richardson / @nealrichardson:
Issue resolved by pull request 9584
#9584