Fix join logp for multivariate RVs

[ricardoV94]

Description

Related Issue

• [x] Closes #7075

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):

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📚 Documentation preview 📚: https://pymc--7215.org.readthedocs.build/en/7215/

[codecov[bot]]

Codecov Report

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

Project coverage is 92.30%. Comparing base (abe7bc9) to head (6dbc885).

Additional details and impacted files

[](https://app.codecov.io/gh/pymc-devs/pymc/pull/7215?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 #7215 +/- ## ======================================= Coverage 92.30% 92.30% ======================================= Files 100 100 Lines 16888 16889 +1 ======================================= + Hits 15588 15589 +1 Misses 1300 1300 ``` | [Files](https://app.codecov.io/gh/pymc-devs/pymc/pull/7215?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pymc-devs) | Coverage Δ | | |---|---|---| | [pymc/logprob/tensor.py](https://app.codecov.io/gh/pymc-devs/pymc/pull/7215?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pymc-devs#diff-cHltYy9sb2dwcm9iL3RlbnNvci5weQ==) | `77.04% <100.00%> (+0.18%)` | :arrow_up: |