Abort if the open fd limit cannot be increased (bp #10064)

[mergify]

This is an automated backport of pull request #10064 done by Mergify

Cherry-pick of 7080fb9 has failed:

On branch mergify/bp/v1.0/pr-10064
Your branch is up to date with 'origin/v1.0'.

You are currently cherry-picking commit 7080fb9b3.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:

	modified:   ledger/src/blockstore.rs

Unmerged paths:
  (use "git add <file>..." to mark resolution)

	both modified:   ledger/src/blockstore_db.rs

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