Make use of new block content permissions in Umami profile

Problem/Motivation

In ✨ Add more granular block content permissions Fixed we're adding new permissions for block content. Some of these might be appropriate for the author and editor roles in the umami demo

Steps to reproduce

Proposed resolution

Decide on appropriate permissions to grant for block content and grant them in the Umami profile roles

Remaining tasks

User interface changes

API changes

Data model changes

Release notes snippet