Update pinned Pint version once new one available

There is currently a bug in Pint which prevents usage of Python 3.13 (see: https://github.com/hgrecco/pint/issues/2065). Apparently a fix is on the way for this shortly, so I will need to be update the pinned version accordingly to ensure that cavcalc can be used in a Python 3.13 environment.

The py:latest stages of the CI will fail until this is resolved.