Originator with long text should be clipped

[compulim]

Fixes #4880.

Changelog Entry

Fixed

• Fixes #4880. Originator with long text should be clipped with ellipsis, by @compulim, in PR #4881

Description

Originator with long text should be clipped with ellipsis.

Specific Changes

• Updated stylesheet of activity status originator
• Removed stylesheet of SlottedActivityStatus because we never use it
• Added tooltip to originator link
• Fixed typo of SelfActivityStatus

• [x] I have added tests and executed them locally
• [x] I have updated CHANGELOG.md
• [x] I have updated documentation

Review Checklist

This section is for contributors to review your work.

• [x] Accessibility reviewed (tab order, content readability, alt text, color contrast)
• [x] ~Browser and platform compatibilities reviewed~
• [x] CSS styles reviewed (minimal rules, no z-index)
• [x] ~Documents reviewed (docs, samples, live demo)~
• [x] ~Internationalization reviewed (strings, unit formatting)~
• [x] ~package.json and package-lock.json reviewed~
• [x] ~Security reviewed (no data URIs, check for nonce leak)~
• [x] Tests reviewed (coverage, legitimacy)