[ML] [k7] Make breadcrumbs more consistent

[spalger]

ML currently mixes tabs and breadcrumbs, and in order to align with the guidelines set up by #25689 we should make the following changes:

• remove breadcrumbs that are repeated by tabs
• sub-pages within tabs will get breadcrumbs
  • going to /app/ml#/settings/calendars_list should have breadcrumbs "Machine Learning / Calendar Management"
  • the "Machine Learning" breadcrumb will always go to the root of Machine Learning (which redirects to "Job Management")

Long term we probably want to move the tab navigation in ML to be more like the side-nav we are implementing in Management. This issue is particularly short on details, and I think there is a decent amount of work to be done, so if someone has time to work on this for 7.0-alpha1 please reach out to me and we can work through the specifics of this. Thanks!

[elasticmachine]

Pinging @elastic/ml-ui

[spalger]

Closed by #26774