mgr/dashboard: fix notification and tearsheet UI issues

- Add Carbon typography classes to running tasks section
- Fix tearsheet footer cutoff by adding min-height: 0 to grid wrapper
- Add launch icon to View in Prometheus link
- Restrict notification detail width to prevent overflow
- Render HTML in notification detail view, strip tags in list preview
- Add gap between timestamp and View more in toast notifications

Signed-off-by: Afreen Misbah <afreen@ibm.com>