fix(Select): add className passed to component to top div

[eszthoff]

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. Use imperative, present tense in your commit description ("change", not "changed" or "changes") without uppercases or period (.) at the end.

Checklist

• The implementation has been manually tested and complies with Textkernel browser support guidelines
• The implementation complies with accessibility standards.
• The component has a displayName defined.
• The component comes with a detailed PropTypes (and defaultProps) definition.
• Component PropTypes are sufficiently described / documented.
• There is a story in Storybook.