Closes # (if applicable).

Changes proposed in this Pull Request

Add co2 storage shadow price to metrics.csv output file

Checklist

• I tested my contribution locally and it seems to work fine.
• Code and workflow changes are sufficiently documented.
• [N/A] Changed dependencies are added to envs/environment.yaml.
• [N/A] Changes in configuration options are added in all of config.default.yaml.
• [N/A] Changes in configuration options are also documented in doc/configtables/*.csv.
• A release note doc/release_notes.rst is added.