The `PROPERTY_USAGE_READ_ONLY` flag only makes the property read-only in the inspector, but the property also has the `PROPERTY_USAGE_NO_EDITOR` flag which means it won't show up in the inspector. So it does nothing, while still making it editable from scripting.
To make it read-only for scripting too, this PR removes the setter from the `PropertyInfo`. And since the `set_capture_included` method is now unused, it was also removed.