add more flexibility to compile_run_output

[pat-schmitt]

In this PR I added more flexibility to compile_run_output. Now it is possible to compile outputs with different data variables. This is mainly needed for the new minimum thickness strategy during the dynamic melt_f calibration. But maybe could be useful in the future.

I have adapted for 2d and 3d variables (for monthly or daily hydro output) and added a test for both cases.

Closes #1561

• Tests added/passed
• Fully documented
• Entry in whats-new.rst

[pat-schmitt]

With these changes, I also could delete the kwarg make_compatible in run_until_and_store.
I introduced it to compile runs with different spinup strategies together. As fixed_geometry_spinup is the fallback for dynamic spinup and has the additional data variable is_fixed_geometry_spinup. With make_compatible I added is_fixed_geometry_spinup as a dummy data variable to all runs, even if no fixed geometry spinup is performed. This is not necessary anymore, with the larger flexibility of compile_run_output.

[fmaussion]

OK merging now to test - please add the remaing TODOs in subsequent PR