Add test for make_summary rule

[pz-max]

The make summary rule is breaking sometimes e.g. https://github.com/pypsa-meets-earth/pypsa-earth/pull/764

• We should add the make-summary rule to the CI-linux workflow here: https://github.com/pypsa-meets-earth/pypsa-earth/blob/main/.github/workflows/ci-linux.yaml.
• add a test for the scenario management rule run_all_scenarios and normal execution rule solve_all_networks

[ekatef]

Hello @DhanshreeA! Thanks a lot for willing to tackle this issue. Please feel free to ping us whenever you have any questions.