Update Topic empty states
What does this MR do and why?
- Show EmptyState when there are no topics.
- Show EmptyResult when there are no search results.
- Migrate header to PageHeadingComponent.
MR acceptance checklist
Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.
Screenshots or screen recordings
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How to set up and validate locally
- Go to http://gdk.test:3000/admin/topics
- Remove topics, if you have any
- [See EmptyState] on this page
- Go to http://gdk.test:3000/explore/projects/topics
- [See EmptyState] on this page
- Go back
- Create a topic
- Search for a non-existing topic
- [See EmptyResult] on this page
- Go to http://gdk.test:3000/explore/projects/topics
- Search for a non-existing topic
- [See EmptyResult] on this page