[NNCF] Experimental common backend: Replace (openvinotoolkit#3249)

Changes:

Call to following class method in
nncf/common/graph/layer_attributes.py was replaced with call to its
corresponding self-contained legacy function in
nncf/common/graph/utils.py:
- layer_attributes.get_target_dim_for_compression ->
get_target_dim_for_compression_legacy(
    layer_attributes: WeightedLayerAttributes)

Locations in /nncf/experimental/common/pruning/
  - nodes_grouping.py

Reason for changes:

(openvinotoolkit#3249) Torch and Tensorflow backend-specific methods need to be removed
from common layer attributes and all related calls need to be replaced
by their corresponding legacy function calls

Author: shumaari

nncf/experimental/common/pruning/nodes_grouping.py

@@ -18,6 +18,7 @@
 from nncf.common.graph.graph import NNCFNode
 from nncf.common.graph.layer_attributes import ConvolutionLayerAttributes
 from nncf.common.graph.layer_attributes import LinearLayerAttributes
+from nncf.common.graph.utils import get_target_dim_for_compression_legacy
 from nncf.common.pruning.mask_propagation import MaskPropagationAlgorithm
 from nncf.common.pruning.utils import PruningOperationsMetatypeRegistry
 from nncf.experimental.common.graph.netron import save_for_netron
@@ -76,7 +77,7 @@ def get_pruning_groups(
     roots = {}
     for node in all_nodes_to_prune:
         assert isinstance(node.layer_attributes, (LinearLayerAttributes, ConvolutionLayerAttributes))
-        pruning_dim = node.layer_attributes.get_target_dim_for_compression()
+        pruning_dim = get_target_dim_for_compression_legacy(node.layer_attributes)
         output_tensors_shapes = [x.tensor_shape for x in graph.get_output_edges(node)]
         assert not len(set(output_tensors_shapes)) > 1, node.node_name
         output_tensors_shape = output_tensors_shapes[0]