Missing permissions to read Org/Members lead to skipped reminders

[bbaga]

Describe the bug
When the search-prs-by-reviewers used to filter for teams and the application doesn't have permission to read org membership information, the search will fail which will cause the notification task to be skipped.

To Reproduce
Remove the the Organization/Members read permission and use the search-prs-by-reviewers source to search for teams.

Expected behavior
Instead of skipping the whole notification, the issue should be logged and the rest of the results should be shown.

Additional context
Documentation should be updated with the required permissions.

Version/Tag: 0.11.0-beta.5