Picker - handle JS API column types in display labels

[bmingles]

#1858 is implementing Table support in the Picker. Handling of data types is pretty naive at the moment and will need to be able to handle additional column types (DateWrapper, Long, etc.)

Current implementation looks like this:

function formatValue(value: unknown): string | number | boolean {
  if (
    typeof value === 'string' ||
    typeof value === 'number' ||
    typeof value === 'boolean'
  ) {
    return value;
  }

  // TODO: Add better support for different data types #1889
  return String(value);
}