Deprecate dummy enterprise key 2/2 (#21328)

Following [1/2](https://github.com/twentyhq/twenty/pull/20890)

Now that all usages of hasValidEnterpriseKey has been removed in prod
and deployed, we can safely remove it altogether.

---------

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

packages/twenty-front/src/modules/object-metadata/hooks/__tests__/useColumnDefinitionsFromObjectMetadata.test.ts

@@ -35,7 +35,6 @@ describe('useColumnDefinitionsFromObjectMetadata', () => {
       allowImpersonation: false,
       subdomain: 'test',
       activationStatus: WorkspaceActivationStatus.ACTIVE,
-      hasValidEnterpriseKey: false,
       hasValidSignedEnterpriseKey: false,
       hasValidEnterpriseValidityToken: false,
       metadataVersion: 1,