Add translated languages to the language picker

[ChrisJohnNOAA]

This is based on @turnbullerin 's work here: turnbullerin/erddap@main...language_picker_fix

Fixes #168

Type of change

• [ X ] Bug fix (non-breaking change which fixes an issue)

Checklist before requesting a review

• [ X ] I have performed a self-review of my code
• [ X ] My code follows the style guidelines of this project
• [ X ] I have commented my code, particularly in hard-to-understand areas
• [ X ] I have made corresponding changes to the documentation
• [ X ] My changes generate no new warnings
• [ X ] I have added tests that prove my fix is effective or that my feature works
• [ X ] New and existing unit tests pass locally with my changes