Allow passing dims to `Potential`

[ricardoV94]

Not important for InferenceData, since potentials don't produce any values that remain in the trace (unless a user wraps them in a Deterministic, which already accept dims), but it would be neat for graphviz.

It's a simple as forwarding dims here:

pymc/pymc/model.py

Line 2052 in 562e51e

model.add_named_variable(var)

[Raj-Parekh24]

Hi @ricardoV94,

I have seen that this issue has been open for a long time and another member has raised no PR. I have started working on it and following the steps suggested by you.

The PR for this issue is #6576.

After solving the issue, I am thinking about whether a new test case is required to check the function working with dims.

Please review the work and suggest changes accordingly.