Update poolInfoUtils.borrowerInfo to return thresholdPrice

[MikeHathaway]

Description

update poolInfoUtils.borrowerInfo interface

Intended for consumption by Subgraph.

Purpose

Impact

Tasks

• [ ] Changes to protocol contracts are covered by unit tests executed by CI.
• [ ] Protocol contract size limits have not been exceeded.
• [ ] Gas consumption for impacted transactions have been compared with the target branch, and nontrivial changes cited in the Impact section above.
• [ ] Scope labels have been assigned as appropriate.
• [ ] Invariant tests have been manually executed as appropriate for the nature of the change.