feat(Table): Style `DropdownMenu` inside of `ActionColumn` in `Table`

[r100-stack]

Co-authored-by: adamhock adamhock@users.noreply.github.com

Closes #730.

• Can now pass className or style as props to ActionColumn to style the inner DropdownMenu

  ActionColumn({
  columnManager: {
  dropdownMenuProps: {
    className: '', // To customize styling of DropdownMenu in ActionColumn
    style: {}, // To customize styling of DropdownMenu in ActionColumn
  },
  },
  }),

• The DropdownMenu has a default max-height: 315px. This can be overridden if a custom style or className is provided
  • NOTE: This hardcoded max-height will hopefully be included in the CSS repo's .iui-scroll class. The DropdownMenu already uses the .iui-scroll class, so migrating to this way is easy.

Checklist

• [x] Add meaningful unit tests for your component (verify that all lines are covered)
• [x] Verify that all existing tests pass
• [x] Add component features demo in Storybook (different stories)
• [x] Approve test images for new stories
• [x] Add screenshots of the key elements of the component

Screenshots

style: {}: If no custom style/className is passed, the DropdownMenu has a max-height: 315px.

style: { maxHeight: 'unset', backgroundColor: 'purple' }