InlineAlert: Fix background color and clean up stories

[reidbarber]

• Fixes background to match Spectrum designs
• Removes extra stories
• Adds dynamic story, and adds to Form story
• Updates some 'In-line' in descriptions to 'Inline' to match docs

✅ Pull Request Checklist:

• Included link to corresponding React Spectrum GitHub Issue.
• Added/updated unit tests and storybook for this change (for new code or code which already has tests).
• Filled out test instructions.
• Updated documentation (if it already exists for this component).
• Looked at the Accessibility Practices for this feature - Aria Practices

📝 Test Instructions:

🧢 Your Project:

[ktabors]

Only "concern" is that when the Header text is the same as the variant string it says the same word twice. That is an issue for the developing team... wondering if we'll get complaints.

[reidbarber]

Yeah, I think apps should hopefully use more specific titles.

[rspbot]

Build successful! 🎉

• View the storybook
• View the storybook-17
• View the storybook-16
• View the documentation

[rspbot]

## API Changes

unknown top level export { type: 'identifier', name: 'Column' }
unknown top level export { type: 'identifier', name: 'Column' }
unknown type { type: 'link' }
unknown type { type: 'link' }
unknown type { type: 'link' }
unknown type { type: 'link' }
unknown type { type: 'link' }
unknown type { type: 'link' }