Bump the shape lib to match the upstream functions currently in PyTorch

[qedawkins]

Bumps the shape library:

• The function signature for aten.arange.start_step was out of date
• upstream_shape_functions.mean_dim -> upstream_shape_functions.sum_mean_dim

[qedawkins]

It looks like it is failing due to the regression test which will be reverted by #1230. I'll just exclude that update for now.

[ramiro050]

@qedawkins, thanks for fixing this! I just wanted to mention that I had already opened a PR making these fixes #1217. For bump style changes like these, it's important to check if no opened PRs already address them to avoid overlap work.

[qedawkins]

@qedawkins, thanks for fixing this! I just wanted to mention that I had already opened a PR making these fixes #1217. For bump style changes like these, it's important to check if no opened PRs already address them to avoid overlap work.

Sorry I completely missed that you already had an open PR! Someone was having issues with the shape functions and I realized there was a desync with PyTorch so after a quick approval from Sean we ended up here. Again apologies for the confusion and I'll be paying closer attention moving forward.

As an aside, I'm thinking we aren't using issue/PR labels very well and it could help to avoid these kinds of mishaps. Might be worth briefly discussing at the next developer meeting.