Switch between cloud providers in cluster creation screen

What does this MR do?

As cluster is created, leave provider buttons visible on top so that user can switch providers if desired.

Extras

Make header sizes more consistent

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Closes #34802 (closed)