SelectControl: Deprecate 36px default size

[hbhalodia]

Part of #65751

What?

Deprecate the 36px default size on SelectControl.

Testing Instructions

• Unit tests pass
• Storybook stories should not log console warnings
• All code snippets in documentation (JSDoc, Storybook, README) should have the __next40pxDefaultSize prop enabled

[github-actions]

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Co-authored-by: hbhalodia <[email protected]>

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[github-actions]

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