chore: Bump IAVL Version to v0.19.7

[mattverse]

Description

Bumps IAVL version to v0.19.7, fixes concurrency issue. Resolved API break that was from v0.19.4 -> v0.19.5

Reviewers Checklist

All items are required. Please add a note if the item is not applicable and please add your handle next to the items reviewed if you only reviewed selected items.

I have...

• [ ] confirmed the correct type prefix in the PR title
• [ ] confirmed ! in the type prefix if API or client breaking change
• [ ] confirmed all author checklist items have been addressed
• [ ] reviewed state machine logic
• [ ] reviewed API design and naming
• [ ] reviewed documentation is accurate
• [ ] reviewed tests and test coverage
• [ ] manually tested (if applicable)