Purpose of this merge is to avoid having to define custom activity types for
each step of HR onboarding plan. This is done by adding a summary field
on hr activities, allowing to use default Todo activity type and customize
directly the summary itself.
Using custom activity types is still possible. Here we allow to avoid noise
and having too much activity types defined as most of those activities can
be simulated using the default Todo.
People can still define and use their own activity types if necessary and
required in their daily workflow.
Commit linked to task ID 1923387 and PR #30235.