Remove TypeInfo

[Tpt]

Remove the TypeInfo enum and the FromPyObject::type_input and IntoPyObject::type_output functions. They are replaced by the PyStaticExpr enum and the FromPyObject::INPUT_TYPE and the IntoPyObject::OUTPUT_TYPE associated constants.

The TypeInfo enum is unused at my knowledge. pyo3-stub-gen does not rely on it but on their own type.

[bschoenmaeckers]

Nice cleaning up!