[Python] Remove TObject __eq__ pythonization

[guitargeek]

The TObject __eq__ pythonization calls TObject::Equals(), which by default does a pointer comparison. That can be very confusing for Python users.

[vepadulano]

Just a fly-by thought, this pythonization has been around for so many years that, while I still strongly believe its current implementation is buggy, I am afraid this will introduce a backwards-incompatible behaviour far, far worse than #19061. One possible way to mitigate this is to have a check that if there is no operator == implementation (or equivalent) for a class, then we can raise an informative exception. Actually, we should probably just raise a warning and declare a deprecation phase for this. Also, note that while the discussion at #19061 is regarding TH1 classes and derived only, this PR is going to have effects for every TObject derived class.