Improve mode shape coefficients for OpenFAST, especially for 2nd modes

[gbarter]

Purpose

Thanks to an Issue posted in the 22-MW repo, I started to dig deeper into the generation of the mode shape coefficients for OpenFAST by WISDEM and found a possibility for mistakes to arise. After improving the WISDEM logic and approach, we found that the new mode shapes are nearly identical for the first mode, but are definitely improved for the second mode.

Note that this change only impacts OpenFAST ElastoDyn users (both blade and tower).

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

• 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 added necessary documentation