Update buttons on GroupsController#show

What does this MR do?

Updates the buttons on GroupsController#show

• Space between the dropdown and buttons should be 8px.
• Dropdown should left align with the rest of the UI at the small breakpoints.
• Change success buttons to the confirm variant.

Screenshots

Before	After

Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

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Security

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Related to #273294 (closed)