Resources code example has confilcting instructions

**Your Godot version:** 4.1.1 stable, 3.5, 3.6

**Issue description:**

Unter "Creating your own Resources", in the first example script, it says without further explanation:

```
# Make sure that every parameter has a default value.
# Otherwise, there will be problems with creating and editing
# your resource via the inspector.
```

But the very same example script does not have any default values. Very confusing. Also "otherwise there will be problems" seems to me like a very imprecise explanation for a documentation document. As a user I would like to make an informed decision, so what problems exactly?

**URL to the documentation page:**
https://docs.godotengine.org/en/stable/tutorials/scripting/resources.html#creating-your-own-resources