Add longrun forced by ERA5 data running for 10-20 years

[juliasloan25]

We want to run the full land model (soil + canopy + snow). This is a useful step as we move towards coupling the full land model with atmos, as it will demonstrate the stability of this model on a long timescale.

We will base the longrun off of land.jl, but with longer simulation length. This could be run weekly so that we maintain the stability of the simulation as we continue to develop our code - we would want a new pipeline for this.

Requires #902
Part of #859