Remove lodash get from class names in the tooling components

[janechu]

Convert the managed classes in the tooling components to use the classNames utilities that the @microsoft/fast-components-base-react uses so that there is not so much over-use of the lodash get utility.

classNames can be imported as a secondary import from the @microsoft/fast-web-utilities package.

This should improve perf of the tooling.

[nicholasrice]

managedClasses should be added to the defaultProps object:

public static defaultProps = { managedClasses: {}}

[janechu]

This has been done on the Form component with #2280, still needed for the Navigation and NavigationMenu.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[chrisdholt]

closed by #3517