Describe the bug

When add an attachment to a process, if the modal is opened after an error, the error message is shown in the modal.

To Reproduce

1. Go to Admin dashboard and go to a process.
2. Go to 'Attachments' in secondary sidebar.
3. Press 'New attachment' button.
4. Click 'Create attachment' to bring up 'cannot be blank' error message and error flash.
5. now try to 'Add file'.
6. See error.

Expected behavior

I would expect for the error message not to show on the modal.

Screenshots

Stacktrace

No response

Extra data

• Device: laptop
• Device OS: ubuntu
• Browser: chrome
• Decidim Version: develop

Additional context

No response