Allow EnhancedResource.resolve to work just like .of for objects

Not requiring the `ResourcesHost` service to exist.
So
```
EnhancedResources.of(User)
EnhancedResources.resolve(User)
```
both work even if the app is not booted.

I don't have a concrete use case for this;
it just feels like the right thing to do

Author: CarsonF

src/common/resource.dto.ts

@@ -107,6 +107,9 @@ export class EnhancedResource<T extends ResourceShape<any>> {
   >();
 
   static resolve(ref: ResourceLike) {
+    if (ref && typeof ref !== 'string') {
+      return EnhancedResource.of(ref);
+    }
     if (!EnhancedResource.resourcesHost) {
       throw new ServerException('Cannot resolve without ResourcesHost');
     }