Bump minimum required Git version to v2.33.0

In Git v2.33.0, we can make use of object type filters in git-cat-file(1). Given that git-cat-file(1) is such a huge burden right now and that the object type filter can significantly improve performance and also enable new and simpler pipelines, we should bump the minimum required version to v2.33.0.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information