build: manually update PyTorch version (#4231)

This commit sets the PyTorch and TorchVision versions to nightly release
2025-06-15.

This commit also disables a check for the test
`test_broadcast_unit_dim_to_dynamic_with_unchanged_dim_dynamic` in
`symbolic_shape_expr_test.py` because it generates different outputs for
the torch stable and nightly versions. The check can be re-enabled once
the nightly changes become part of the stable torch version.

---------

Signed-off-by: Vivek Khandelwal <vivekkhandelwal1424@gmail.com>

Author: vivekkhandelwal1

pytorch-hash.txt

@@ -1 +1 @@
-724da4eecc6c0ae561efbdcb371ac3f07a7ba8bd
+74d0136772a9564c77360c17c849c3a368fa3e8f

pytorch-requirements.txt

@@ -1,3 +1,3 @@
 -f https://download.pytorch.org/whl/nightly/cpu/torch/
 --pre
-torch==2.8.0.dev20250609
+torch==2.8.0.dev20250615

test/python/fx_importer/symbolic_shape_expr_test.py

@@ -371,7 +371,9 @@ def forward(self, x: torch.Tensor, y: torch.Tensor) -> torch.Tensor:
 # CHECK:        torch.bind_symbolic_shape %[[ARG0]], [%[[S0]]], affine_map<()[s0] -> (1, s0)> : !torch.vtensor<[1,?],f32>
 # CHECK:        torch.bind_symbolic_shape %[[ARG1]], [%[[S1]]], affine_map<()[s0] -> (s0)> : !torch.vtensor<[?],f32>
 # CHECK:        %[[EXPAND:.+]] = torch.aten.expand %[[ARG0]], {{.*}}, {{.*}} : !torch.vtensor<[1,?],f32>, !torch.list<int>, !torch.bool -> !torch.vtensor<[?,?],f32>
-# CHECK:        torch.bind_symbolic_shape %[[EXPAND]], [%[[S0]], %[[S1]]], affine_map<()[s0, s1] -> (s1, s0)> : !torch.vtensor<[?,?],f32>
+# TODO: Re-enable checks once the nightly changes are in stable.
+# The difference is that the nightly version generates a symbolic shape expression for the expand op with the order of dimensions swapped.
+# CHECK-DISABLED:        torch.bind_symbolic_shape %[[EXPAND]], [%[[S1]], %[[S0]]], affine_map<()[s0, s1] -> (s0, s1)> : !torch.vtensor<[?,?],f32>
 # CHECK:        return %[[EXPAND]] : !torch.vtensor<[?,?],f32>
 def test_broadcast_unit_dim_to_dynamic_with_unchanged_dim_dynamic():
     class BroadcastUnitDimToDynamicWithUnchangedDimDynamic(torch.nn.Module):

torchvision-requirements.txt

@@ -1,3 +1,3 @@
 -f https://download.pytorch.org/whl/nightly/cpu/torchvision/
 --pre
-torchvision==0.23.0.dev20250609
+torchvision==0.23.0.dev20250615