Refactor tenant ORM integration (#1650)

* Refactor tenant ORM integration

* fix tests

server/src/tenant/metadata/metadata.service.spec.ts

@@ -0,0 +1,19 @@
+import { Test, TestingModule } from '@nestjs/testing';
+
+import { MetadataService } from './metadata.service';
+
+describe('MetadataService', () => {
+  let service: MetadataService;
+
+  beforeEach(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [MetadataService],
+    }).compile();
+
+    service = module.get<MetadataService>(MetadataService);
+  });
+
+  it('should be defined', () => {
+    expect(service).toBeDefined();
+  });
+});