Fix error in warn_treedepth when using multiple NUTS samplers

[ricardoV94]

Description

Fix issue reported in https://discourse.pymc.io/t/valueerror-the-truth-value-of-an-array-with-more-than-one-element-is-ambiguous-given-at-the-end-of-sampling/13875/3

Checklist

• [x] Checked that the pre-commit linting/style checks pass
• [x] Included tests that prove the fix is effective or that the new feature works
• [x] Added necessary documentation (docstrings and/or example notebooks)
• [x] If you are a pro: each commit corresponds to a relevant logical change

Type of change

• [ ] New feature / enhancement
• [x] Bug fix
• [ ] Documentation
• [ ] Maintenance
• [ ] Other (please specify):

---

📚 Documentation preview 📚: https://pymc--7182.org.readthedocs.build/en/7182/

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 92.24%. Comparing base (6c6fd13) to head (6a12657).

Additional details and impacted files

[](https://app.codecov.io/gh/pymc-devs/pymc/pull/7182?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pymc-devs) ```diff @@ Coverage Diff @@ ## main #7182 +/- ## ======================================= Coverage 92.24% 92.24% ======================================= Files 100 100 Lines 16887 16887 ======================================= Hits 15577 15577 Misses 1310 1310 ``` | [Files](https://app.codecov.io/gh/pymc-devs/pymc/pull/7182?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pymc-devs) | Coverage Δ | | |---|---|---| | [pymc/stats/convergence.py](https://app.codecov.io/gh/pymc-devs/pymc/pull/7182?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pymc-devs#diff-cHltYy9zdGF0cy9jb252ZXJnZW5jZS5weQ==) | `97.43% <100.00%> (ø)` | | | [pymc/step\_methods/hmc/nuts.py](https://app.codecov.io/gh/pymc-devs/pymc/pull/7182?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pymc-devs#diff-cHltYy9zdGVwX21ldGhvZHMvaG1jL251dHMucHk=) | `97.27% <ø> (ø)` | |

[ricardoV94]

Thanks for the review @junpenglao! However, I'm slightly disappointed you didn't say "LGTM"