fix: Change init input of Memorize from Param to Data input category

Context

After discussing it with @cmoineau, it appeared that having the initalization input of Memorize categorized as a Param is a mistake. Param should refer to learnable parameters, which is obviously not the case here.

Fix #222 (closed)

src/operator/Memorize.cpp

@@ -76,7 +76,7 @@ void Aidge::Memorize_OpImpl::forward() {
 const std::string Aidge::Memorize_Op::Type = "Memorize";
 
 Aidge::Memorize_Op::Memorize_Op(const std::uint32_t endStep)
-    : OperatorTensor(Type, {InputCategory::Data, InputCategory::Param}, 2),
+    : OperatorTensor(Type, {InputCategory::Data, InputCategory::Data}, 2),
         mAttributes(std::make_shared<Attributes_>(
                     attr<MemorizeAttr::ScheduleStep>(0),
                     attr<MemorizeAttr::ForwardStep>(0),