Refactored RV _print_name to long names

[shreyas3156]

Motivation for these changes

Closes #204

Implementation details

Renamed the RV names in _print_name to their long versions.

Checklist

• Explain motivation and implementation 👆
• Make sure that the pre-commit linting/style checks pass.
• Link relevant issues, preferably in nice commit messages.
• The commits correspond to relevant logical changes. Note that if they don't, we will rewrite/rebase/squash the git history before merging.
• Are the changes covered by tests and docstrings? No
• Fill out the short summary sections 👇

Major / Breaking Changes

• none

[larryshamalama]

Looks good to me. Thanks @shreyas3156 for your help! :)

Minor note for ourselves: we would have to adapt tests from pymc/tests/test_printing.py accordingly once a new release for PyTensor is cut/pinned for PyMC.

[ricardoV94]

Thanks @shreyas3156!