Improve performance twenty orm (#6691)

## Context

As we grow, the messaging scripts are experiencing performance issues
forcing us to temporarily disable them on the cloud.
While investigating the performance, I have noticed that generating the
entity schema (for twentyORM) in the repository is taking ~500ms locally
on my Mac M2 so likely more on pods. Caching the entitySchema then!

I'm also clarifying naming around schemaVersion and cacheVersions ==>
both are renamed workspaceMetadataVersion and migrated to the workspace
table (the workspaceCacheVersion table is dropped).

packages/twenty-front/src/testing/mock-data/users.ts

@@ -63,7 +63,7 @@ export const mockDefaultWorkspace: Workspace = {
   ],
   createdAt: '2023-04-26T10:23:42.33625+00:00',
   updatedAt: '2023-04-26T10:23:42.33625+00:00',
-  currentCacheVersion: '1',
+  metadataVersion: 1,
   currentBillingSubscription: {
     __typename: 'BillingSubscription',
     id: '7efbc3f7-6e5e-4128-957e-8d86808cdf6a',
@@ -71,6 +71,8 @@ export const mockDefaultWorkspace: Workspace = {
     status: SubscriptionStatus.Active,
   },
   workspaceMembersCount: 1,
+  databaseSchema: '',
+  databaseUrl: '',
 };
 
 export const mockedWorkspaceMemberData: WorkspaceMember = {