Add LUS property back to ConFIG

- With the new way we generate matrices, this test seems to pass.

Author: ValerianRey

docs/source/docs/aggregation/index.rst

@@ -40,7 +40,7 @@ In TorchJD, an aggregator is a class that inherits from the abstract class
      - |yes|
    * - :doc:`ConFIG <config>`
      - |no|
-     - |no|
+     - |yes|
      - |yes|
    * - :doc:`Constant <constant>`
      - |no|

tests/unit/aggregation/test_config.py

@@ -3,13 +3,13 @@
 
 from torchjd.aggregation import ConFIG
 
-from ._property_testers import ExpectedStructureProperty
+from ._property_testers import ExpectedStructureProperty, LinearUnderScalingProperty
 
 
 # For some reason, some permutation-invariance property tests fail with the pinv-based
 # implementation.
 @mark.parametrize("aggregator", [ConFIG()])
-class TestConfig(ExpectedStructureProperty):
+class TestConfig(ExpectedStructureProperty, LinearUnderScalingProperty):
     pass