Better support for scrollable roadmaps in dashboards and shared webpages

What is the challenge?

For roadmap views displayed in dashboards and shared webpages, horizontal scrolling is creating several bugs:
- In shared webpages, the header and body of the roadmap can be horizontally misaligned leading to dates not matching the position of the records.

- In dashboards, scrolling the body of a roadmap does not scroll the header

Those bugs do not happen in the native roadmap page.