Closes https://github.com/twentyhq/core-team-issues/issues/526
(for reminder:
1. Make defaultRoleId non-nullable for an active workspace
2. Remove permissions V1 feature flag
3. Set member role as default role for new workspaces
About 1.:
An active workspace's defaultRoleId should never be null.
We can't rely on a simple postgres NOT NULL constraint as defaultRoleId
will always be initially null when the workspace is first created since
the roles do not exist at that time.
Let's add a more complex rule to ensure that
About 3.:
In the first phase of our deploy of permissions, we chose to assign
admin role to all existing users, not to break any existing behavior
with the introduction of the feature (= existing users have less rights
than before).
As we deploy permissions to all existing and future workspaces, let's
set the member role as default role for future workspaces.
)
A user should not be able to delete their account if they are the last
admin of a workspace.
It means that if a user wants to sign out of twenty, they should delete
their workspace, not their account
