added perennials and green biorefining in compile_cost_assumptions.py

[BertoGBG]

Closes # (if applicable).

Changes proposed in this Pull Request

This PR added the technology perennials and green biorefining as "perennials gbr". The technology produces additional biogas from perennial crops.
the changes are implemented in compile_cost_assumptions.py via the function add_perennials_gbr (which is structured similarly to add_carbon_capture)

Checklist

• [Y ] Code changes are sufficiently documented; i.e. new functions contain docstrings and further explanations may be given in doc.
• [ Y] Data source for new technologies is clearly stated.
• Newly introduced dependencies are added to environment.yaml (if applicable).
• A note for the release notes doc/release_notes.rst of the upcoming release is included.
• [Y ] I consent to the release of this PR's code under the GPLv3 license.

[fneum]

Could you add a little more detail in the commentary how the concrete value for the investment was obtained from the paper? Thanks!

[BertoGBG]

I added comments about the investments and VOM (mostly the reference table), the code/function with in compile_cost_assumptions.py contains direct reference to the tables in the source ( and the link to the course as a comment) so that the calculations are traceable.

[euronion]

Hej @BertoGBG , is the PR ready for another round of review?

[BertoGBG]

The PR was just rebased and it is ready for review.

Heads up: CI on master itself is currently failing — test_get_sheet_location, test_get_data_from_dea, and test_add_carbon_capture fail on a clean master checkout (KeyError: ('cement capture', 'Variable O&M')).
My rebased PR inherits this, so their CI failure isn't from my changes — the snakemake build and output
regeneration pass. They should go green once master's tests are fixed.