tabs: update alignment section on usage tab

[laurenmrice]

Auto-width and Grid aware tabs guidance

Update the Alignment section on the Usage tab to include the following:

• Add initial guidance about when to use grid aware tabs. Ref issue #13351
• Think about whether to add do/don't guidance and imagery.
• See if we need to revisit any current images/content and if we could expand on them to make the information more clear.
• Take off informational inline notification, this has been implemented.