Feat/operator squeeze unsqueeze

Context

see issue : aidge_core#65 (closed)

Refactored tests for onnx

• Test_import_export can now easily run multiple networks
• node register has been completed

replaced all prints by logging

Fixed onnx node opset retrieval

Done in 190c2d9f

Previously the opset of the model was retrieved with model.ir_version, which is .... I do not know what it is but this is named intermediate representation and not opset.

Opsets have to be retrieved via model.opset_import. Its a list [opset] (/protoobject) that contains :

1. a domain name
2. an associated opset

Each node is attached to a domain name which bind them to a given opset.

This allos to use multiple opsets in a given model.

More on that here : http://onnx.ai/sklearn-onnx/auto_tutorial/plot_cbegin_opset.html

aidge_onnx/node_export/aidge_converters/unsqueeze.py

+"""
+Copyright (c) 2024 CEA-List
+
+This program and the accompanying materials are made available under the
+terms of the Eclipse Public License 2.0 which is available at
+http://www.eclipse.org/legal/epl-2.0.
+
+SPDX-License-Identifier: EPL-2.0
+"""
+import aidge_core
+import onnx
+from onnx import helper
+from aidge_onnx.node_export import auto_register_export
+
+@auto_register_export("Unsqueeze")
+def export_unsqueeze(
+    aidge_node: aidge_core.Node,
+    node_inputs_name,
+    node_outputs_name,
+    verbose: bool = False) -> None:
+    aidge_operator = aidge_node.get_operator()
+    onnx_node = helper.make_node(
+        name=aidge_node.name(),
+        op_type="Unsqueeze",
+        inputs=node_inputs_name,
+        outputs=node_outputs_name,
+    )
+
+    onnx_node.attribute.append(
+        helper.make_attribute(
+            "axis",
+            aidge_operator.get_attr("Axis")
+    ))
+    return [onnx_node]