Identity skip + args for edge gated block

[samwaltonnorwood]

Adds the "lifted_skip" function which acts as a direct residual connection, zero-padding as necessary to match new irreps in the output of EquivariantProductBasisBlock.
Also adds arguments to the InteractionBlock class to support edge gating for OCP.

[samwaltonnorwood]

@abhshkdz The lifted_skip operation needs to be revised to fix the bug you're seeing. The setup I developed this on was slightly different and ensured node_feats_irreps.dim <= hidden_irreps.dim, so it errs in the opposite case. This should fix it:

``` class lifted_skip(torch.nn.Module):
    def __init__(self, irreps_in: o3.Irreps, irreps_out: o3.Irreps) -> None:
        super().__init__()
        self.in_dim = o3.Irreps(irreps_in).dim
        self.out_dim = o3.Irreps(irreps_out).dim
        self.pad = True
        if self.in_dim >= self.out_dim:
            self.pad = False
        
    def forward(self, tensor: torch.Tensor) -> torch.Tensor:
        batch, _ = tensor.shape
        if self.pad:
            template = torch.zeros(batch, self.out_dim, device=tensor.device)
            template[:, :self.in_dim] = tensor
            return template
        else:
            return tensor[:, :self.out_dim]