Update swift-transformers to 0.1.23

[tpae]

I recently merged a PR in swift-transformers to address a critical performance related issue: huggingface/swift-transformers#218

It was released with 0.1.23: https://github.com/huggingface/swift-transformers/releases/tag/0.1.23

Can we make a new tag with this update?

[davidkoski]

Sure, can you make a PR to update Package.swift and the xcodeproj snapshot of the version numbers?