[Guided Onboarding] Remove "Setup Guides" buttons (#208510)

## Summary
This PR removes `Setup Guides` buttons.
Closes: #207026

> [!NOTE]
All the tests in
`src/platform/plugins/shared/guided_onboarding/public/components/guide_panel.test.tsx`
depend on those buttons so it was easier to remove those tests.

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

Author: kowalczyk-krzysztof