Replace 'upload_time' with 'upload-time'

This was due to an inconsistency between uv 0.6.15 and 0.7.0. Either
version can understand a lock file written by the other, but 0.7 will
automatically rewrite it with 'upload-time' whenever it makes a change,
resulting in a huge diff that makes it very hard to see what actually
changed.

astral-sh/uv#13176

Author: millerdev