Timeline: Only renders text

[stevetsanders]

Describe the bug
Timeline only renders text, no boxes or Timeline items

Isolated Example
https://sap.github.io/ui5-webcomponents-react/?path=/story/ui5-web-components-timeline--generated-default-story

To Reproduce
Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots
If applicable, add screenshots to help explain your problem.

UI5 Web Components for React Information
@ui5/webcomponents version: 1.0.0-rc.8
@ui5/webcomponents-react version: v0.10.1
Operating System: windos
Browser: edge (chromium)

Additional context
Add any other context about the problem here.