Remove triangle background settings from options of background wrappers.

[trackleft]

Conditions of satisfaction

• [ ] Ability to make new pages that use triangle bg wrappers disabled https://github.com/az-digital/az_quickstart/blob/main/modules/custom/az_paragraphs/src/Plugin/paragraphs/Behavior/AZTextWithBackgroundParagraphBehavior.php#L74-L77

[joeparsons]

We'll need to figure out what to do with existing content using those background wrappers...