RAL4 configuration script development

Create and test a .conf file that works with the full (new) list of model fields in UM and LFRic as part of RAL4 evaluation.

Steps to do;
- [x] Review CSET conf used for sensitivity testing and modifications required, and test with latest CSET release (Sept26).
- [x] Test past RAL3-LFRic conf with latest CSET release (Sept26) and check failures (if any) are known and understood.
- [ ] Derive a new two case study simulation using new RAL4 model fields and check existing variables and plot types work in CSET [Waiting on implementation].
- [ ] Add additional colorbars for new variables, and ensure they are supported (with some exceptions for time meaned variables), and pull in changes required from sensitivity testing.
- [ ] Test all variables with new functionality (QQ-plots, power spectra, then eventually scores).