Make it clearer what to do after adding a namespace

Problem to solve

From the walkthrough of the existing setup it wasn't clear:

1. When the setup process was complete and or successful
2. If it was successful it wasn't clear what to do next

Proposal

• Leverage the Success variant of the Alert component when a namespace(s) has been added for the first time.

See mockup in Designs section.

See (#232727 (closed)) for an example of entire flow installation flow.

Alert copy:

Namespace successfully linked

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