Local integration for turbine force

[jefalon]

Purpose

This PR adds the feature to create a local integration bubble around each turbine allowing for quicker assemblies. It works by marking the mesh cell in a sphere around each turbine and then labeling them. This way, when integrating or assembling the A matrix, FEniCS only need to assemble a small cluster of DOF per turbine rather than the full global domain. Since the turbine function rapidly go to zero, this approximation should be sound while saving significant compute time.

Type of change

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (non-backwards-compatible fix or feature)
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no API changes)
• Documentation update
• Maintenance update
• Other (please describe)

Testing

The approximation is so good that all the current CI test work using this new integration except for the ALMx2_Unsteady case.

Checklist

• I have run existing tests which pass locally with my changes
• I have added new tests or examples that prove my fix is effective or that my feature works
• I have verified my code additions work in parallel
• I have added necessary documentation