COMPMID-1500: (Nightly) CLIm2ColGrouped std::bad_alloc and crashes

Decrease large sizes as it leads to std::bad_alloc for some shapes

Change-Id: I274ceb65411c0ddef87f11135d7fdddfc89c7651
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/143877
Reviewed-by: Michele DiGiorgio <michele.digiorgio@arm.com>
Tested-by: Jenkins <bsgcomp@arm.com>
diff --git a/tests/datasets/ShapeDatasets.h b/tests/datasets/ShapeDatasets.h
index a1ca983..57bb9d0 100644
--- a/tests/datasets/ShapeDatasets.h
+++ b/tests/datasets/ShapeDatasets.h
@@ -660,9 +660,8 @@
     GroupedIm2ColLargeShapes()
         : ShapeDataset("Shape",
     {
-        TensorShape{ 1921U, 1083U, 12U },
-                     TensorShape{ 641U, 485U, 24U, 3U },
-                     TensorShape{ 799U, 595U, 12U, 4U },
+        TensorShape{ 153U, 231U, 12U },
+                     TensorShape{ 123U, 191U, 12U, 2U },
     })
     {
     }