Operational Reserves error for problems without extendable generators

[ktehranchi]

Checklist

• [X] I am running on an up-to-date pypsa-usa environment. Update via conda env update -f envs/environment.yaml

Issue exisits on what branch

Develop

The Issue

In two places in the operational reserves formulation the model will throw a bug when there are no extendable generators enabled. Line 773 and 805 in solve_network need if statements for cases without extendable generators.

Steps To Reproduce

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Expected Behavior

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Error Message

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Anything else?

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