test: always give extra message when errors are in the scope of autobinding

[robsimmons]

This is an experiment: it may be worth targeting specific error messages instead of coming from the other direction

[leanprover-community-bot]

Mathlib CI status (docs):

• ❗ Batteries/Mathlib CI will not be attempted unless your PR branches off the nightly-with-mathlib branch. Try git rebase 5f561bfee287eaf9f1907c8a9e67bff58acdd242 --onto dd28f005889dd2fcca6fe0638133de561a655ad1. You can force Mathlib CI using the force-mathlib-ci label. (2025-12-04 22:54:09)

[leanprover-bot]

Reference manual CI status:

• ❗ Reference manual CI will not be attempted unless your PR branches off the nightly-with-manual branch. Try git rebase 5f561bfee287eaf9f1907c8a9e67bff58acdd242 --onto d3dda9f6d4428a906c096067ecb75e432afc4615. You can force reference manual CI using the force-manual-ci label. (2025-12-04 22:54:10)