Feature/#1445 adapt dataset gas supply to new scenarios

[cvarela-dlr]

Fixes #1445.

Please review after PR #1517.

Key Changes

• Adapt the Gas_Supply TaskGroup to the new scenarios, primarily enabling the workflow.
• Pending is treatment for reGon2045, with potential updates on reGon2037 parameters.

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[CarlosEpia]

Please merge dev into this branch. Then proceed to merge it into server-run-11-09 so it will be tested for the Germany case.