Remains of serialized content access settings

Problem/Motivation

TypeError in RevokeAccess::updateSettings 🐛 TypeError in RevokeAccess::updateSettings Fixed fixed the code for json content access settings, but there are cases where serialized settings still remain in the database table, maybe due to the former bug (settings seem to be json encoded since the fix).

Proposed resolution

Add hook_update_N to convert remaining serialized settings in content_access database table.