Statistics automatically displayed when creating a new participatory process (0.20)

[paulinebessoles]

Describe the bug
When creating a new participatory process, when I don't check the "Show statistics" box, the statistics are displayed on the user panel anyway. I have to come back in the information sub-menu of the process in the admin panel to uncheck this parameter.

To Reproduce
Steps to reproduce the behavior:

1. Go to the participatory process menu on the admin panel of "http://staging.decidim.codegram.com/admin/participatory_processes"
2. Click on 'New Process'
3. Create a participatory process, with the statistics parameter kept unchecked
4. See error on the user panel after the process was created

Expected behavior
When not checking the "show statistics" parameter, I want the statistics hidden on my process.

Extra data
Device: [Desktop]
Device OS: [Windows 10]
Browser: [Chrome]
Decidim Version: [0.20.0 dev]
Decidim installation: [staging.decidim.codegram.com]

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. @carolromero & @xabier feel free to chime in.