Send Epoch Accounts Hash requests from set_root()

[brooksprumo]

Problem

Epoch Accounts Hash requests are never sent.

Summary of Changes

Send Epoch Accounts Hash requests from bank_forks::set_root().

• Add the ability to specify the request type (so ABS handles EAH with highest priority)
• Add the ability to specify the accounts package type (so AHV handles EAH with highest priority)

[brooksprumo]

@jeffwashington I have to resolve why some local-cluster tests are failing, but I think this PR is good enough to review for direction/design.

I'll mark the PR as "ready for review" once I have all of CI passing, and then properly add you as a reviewer. Feel free to wait until there, or jump in early.