[core] Make the init input of Memorize operator node a `Data` input instead of `Param`

Problem description

Aidge::Memorize_Op::Memorize_Op(const std::uint32_t endStep)
    : OperatorTensor(Type, {InputCategory::Data, InputCategory::Param}, 2),

Currently, Memorize_Op has its input parameter of category Param. This should be changed to Data, as Param refers to learnable parameters.