Reduce dimensions in _stationarity_dims

Author: ValerianRey

tests/unit/aggregation/_inputs.py

@@ -135,11 +135,11 @@ def _generate_semi_orthonormal_complement(Q: Tensor) -> Tensor:
 ]
 
 _stationarity_dims = [
-    (50, 10, 10),
-    (50, 10, 5),
-    (50, 10, 1),
-    (50, 500, 1),
-    (50, 500, 49),
+    (20, 10, 10),
+    (20, 10, 5),
+    (20, 10, 1),
+    (20, 100, 1),
+    (20, 100, 19),
 ]
 
 _scales = [0.0, 1e-10, 1e3, 1e5, 1e10, 1e15]