[TASK] Add tooltip explaining what image extra filters means during Workspace creation

### Certification

- [x] I certify I am an Epic Owner for Kubeflow Notebooks 2.0 and expected to create planning-related issues.

### Description

With the addition of `Show hidden` and `Show redirected` filters when listing images during workspace creation, help texts could be added to make these concepts clear to the user.

### Acceptance Criteria

- [ ] A question mark icon is shown after the `Show hidden` checkbox filter, when hovered it shows the text: "Also show images that were hidden by your cluster administrator."
- [ ] A question mark icon is shown after the `Show redirected` checkbox filter, when hovered it shows the text: "Also show images that have a successor defined by your cluster administrator."

Start in the workspace-creation UI where the image list's Show hidden and Show redirected checkbox filters are rendered, and check how existing question-mark icons or hover help are implemented. Add the two specified explanations and verify that each appears when its icon is hovered; the acceptance criteria define the done state.

Written by the indexing model from the issue text.