Gams gurobi valid solvers fix

[sergey-gusev94]

Fixes # None

Summary/Motivation:

Previously, the configuration did not account for the use of NLP and MINLP when Gurobi was selected as a subsolver within GAMS. This PR ensures that these problem types are properly recognized and supported.

Changes proposed in this PR:

• Added support for NLP and MINLP when Gurobi is used as a subsolver within GAMS.

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[jsiirola]

This is great - and needed. Please:

• reorder the set entries to match the column order from https://www.gams.com/latest/docs/S_MAIN.html#SOLVERS_MODEL_TYPES
• verify the set matches those docs (I believe that RNLP is missing)
• [bonus] would you mind going through that table and verifying the other solvers, too (and add any missing entries)?

[sergey-gusev94]

I have reordered the set entries and added missing solvers.

[jsiirola]

We should probably:

• add a test that verifies that this data structure is correct
• only create this data structure the first time it is needed (maybe move this to a class attribute?)

But, I am fine deferring these for a subsequent PR.