Fix `compute_log_prior` in models with `Deterministics`

[OriolAbril]

Description

The default for var_names in compute_log_likelihood was unobserved_RVs which includes also deterministics. This changes the default to free_RVs.

Related Issue

• [ ] Closes #
• [ ] Related to #

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
• [ ] 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):

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📚 Documentation preview 📚: https://pymc--7168.org.readthedocs.build/en/7168/

[codecov[bot]]

Codecov Report

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

Comparison is base (97a7a00) 92.29% compared to head (34d2a5d) 92.29%.

Additional details and impacted files

[](https://app.codecov.io/gh/pymc-devs/pymc/pull/7168?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 #7168 +/- ## ======================================= Coverage 92.29% 92.29% ======================================= Files 101 101 Lines 16947 16947 ======================================= Hits 15642 15642 Misses 1305 1305 ``` | [Files](https://app.codecov.io/gh/pymc-devs/pymc/pull/7168?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/log\_density.py](https://app.codecov.io/gh/pymc-devs/pymc/pull/7168?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pymc-devs#diff-cHltYy9zdGF0cy9sb2dfZGVuc2l0eS5weQ==) | `98.30% <100.00%> (ø)` | |