Highlight Flex Stops when opening pattern stop

[miles-grant-ibigroup]

One non-blocking thing is when you click on pattern stops in the pattern editor, the regular stops on the map get highlighted in blue (see screenshot below), but not the flex zones, and maybe they should be highlighted too when selected.

Originally posted by @binh-dam-ibigroup in https://github.com/ibi-group/datatools-ui/issues/754#issuecomment-1157766878