Fix for typescript types on the Combobox and SetupAssistant component props

[bolivierjr]

This adds types to the additional event parameters needed for the event props in these components so typescript doesn't fail when type checking. Also a typo fix for the disabled attribute in the options prop type in Combobox.

Fixes #2969

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[bolivierjr]

bump. @interactivellama looking forward on a review to this! This would help us out a lot or anyone else that uses typescript in their projects with slds react.

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This definitely calls for a high five!

[interactivellama]

Thanks @bolivierjr !