[permissions] Enable permissions V1 for all workspaces (#11172)

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.
)

packages/twenty-server/src/engine/api/graphql/graphql-query-runner/interfaces/base-resolver-service.ts

@@ -87,17 +87,9 @@ export abstract class GraphqlQueryBaseResolverService<
           authContext.workspace.id,
         );
 
-      if (
-        featureFlagsMap[FeatureFlagKey.IsPermissionsEnabled] &&
-        objectMetadataItemWithFieldMaps.isSystem === true
-      ) {
+      if (objectMetadataItemWithFieldMaps.isSystem === true) {
         await this.validateSystemObjectPermissionsOrThrow(options);
-      }
-
-      if (
-        featureFlagsMap[FeatureFlagKey.IsPermissionsEnabled] &&
-        !objectMetadataItemWithFieldMaps.isSystem
-      ) {
+      } else {
         await this.validateObjectRecordPermissionsOrThrow({
           operationName,
           options,