feat: support for many padding dynamo converters

[zewenli98]

Description

Support for many padding dynamo converters, including:

torch.ops.aten.pad.default
torch.ops.aten.constant_pad_nd.default
torch.ops.aten.reflection_pad1d.default
torch.ops.aten.reflection_pad2d.default
torch.ops.aten.reflection_pad3d.default
torch.ops.aten.replication_pad1d.default
torch.ops.aten.replication_pad2d.default
torch.ops.aten.replication_pad3d.default
torch.ops.aten._pad_circular.default

Note:

1. Not sure why there're no similar names for torch.ops.aten._pad_circular.default like torch.ops.aten.circular_pad1d.default, but according to PyTorch doc, it does have the similar functionality as reflection and replication, targeting for 2D, 3D, 4D, and 5D inputs.
2. torch.ops.aten.pad.default is a higher-level function to call the other padding functions.

Fixes #2461 #2211

Type of change

• New feature (non-breaking change which adds functionality)

Checklist:

• My code follows the style guidelines of this project (You can use the linters)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas and hacks
• I have made corresponding changes to the documentation
• I have added tests to verify my fix or my feature
• New and existing unit tests pass locally with my changes
• I have added the relevant labels to my PR in so that relevant reviewers are notified

[zewenli98]

Hi @gs-olive, thanks for your review! I just found out a better way to implement paddings, with the help of ISliceLayer with different SliceMode. So I undid the change to slice_op.

[gs-olive]

Overall looks great, added a few style comments and suggested modifications.

[gs-olive]

Looks good to me!