Update build system to Python 3.12

[jsbrittain]

We cannot currently update our build system to the latest (most optimised) version of python (3.12) due to the following:

• originally we were awaiting a fix from node-gyp, detailed here:
  • https://github.com/nodejs/node-gyp/issues/ 2869
  • This emerged since python 3.12 removed the distutils module.
  • node-gyp appear to have pushed a fix, but this needs to be picked up and released as part of node-pty
  • A workaround seems to be to install setuptools in the python environment before executing npm i node-pty
• after implementing the above workaround, postbuild tests fail due to snakemake dependencies

[jsbrittain]

snakemake version 7 does not support python 3.12; so an upgrade to snakemake version 8 is required; however, this is not a trivial update: see #189 .