fix: Fix processExpiration for pool 8

[rackstar]

Context

Closes #1151

See the above issue for detailed info

Changes proposed in this pull request

• Add check in proccessExpirations for pool 8 and rollback lastAccNxmUpdate to prevent underflow

Test plan

• fork test

Checklist

• Rebased the base branch
• Attached corresponding Github issue
• Prefixed the name with the type of change (i.e. feat, chore, test)
• Performed a self-review of my own code
• Followed the style guidelines of this project
• Made corresponding changes to the documentation
• Didn't generate new warnings
• Didn't generate failures on existing tests
• Added tests that prove my fix is effective or that my feature works

Review

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