2722 - Q/A issues for Fontpicker component [v4.24.x]

[EdwardCoyle]

Explain the details for making this change. What existing problem does the pull request solve?
This PR addresses these two issues:

• Changes to settings handling on Toolbar Flex to accommodate passing down Popupmenu settings to an action button caused some AJAX calls not to be properly handled. The logic for passing settings has been changed to correctly target action buttons.
• Fixed the alignment of the dropdown icon on both Edge (Vibrant) and Firefox (Subtle)

Related github/jira issue (required):
Closes #2722

Steps necessary to review your pull request (required):
Pull this branch, build, run the app. Then...

To test the Ajax Calls are working properly:

• Open http://localhost:4000/components/toolbar-flex/example-more-actions-ajax.html?layout=nofrills
• Open the "Menu Button". All of its child items should be prefixed with "Menu Button Option".
• Open the More Actions menu. All of its child items should be prefixed with "AJAX Option"

To test the icon alignment:

• Open http://localhost:4000/components/editor/example-flex-toolbar in Firefox. The general button icon alignment compared to the Fontpicker's should be accurate.
• Open http://localhost:4000/components/editor/example-flex-toolbar?theme=uplift in IE/Edge. The same should be true in these browsers.

[EdwardCoyle]

@Sovia pinging you just to let you know about the short-lived issue with Flex Toolbar / AJAX. The problem was in our 4.24.x branch for about a day or so. This PR should fix it.