Bump/0.29

[Stef-Rousset]

🎩 Description
This PR bumps the extra_user_fields module to 0.29 version of decidim

📌 Related Issues
Related to OpenSourcePolitics/decidim-app#711?

Testing

1. As an admin, go to the Settings in the BO
2. Go to Manage extra user fields
3. Click the checkbox "Enable extra user fields"
4. In the Available extra user field section, choose the fields you want to add and save
5. In the FO, go to "My account'
6. Update your account with the extra user fields infos, and see that it is saved well
7. Log out
8. Create a new account and fill the extra user fields infos and see that it is saved well

Tasks

[Stef-Rousset]

The failing CI is linked to "accessible page" test in /system/account_spec.rb, and is linked to the datepicker. I made corrections to get the accessibility tests ok, by adding acccessible_datepicker.js . The HTML validation test should be fix on the datepicker himself.