Exclude Canvas folder config from site:export
I keep having issues with the Canvas folder config with site templates, getting the error:
```
It is impossible for an item to exist in multiple Folders.
```
I have not really checked but I think the issue is that the folders are created every time you install, they are not carried over from the site template. So then when you re-export, you get duplicates.
The folders are generated based on the SDC (or code component config) at install time, so they shouldn't be included in the site:export.
issue