Describe the bug
Accessing meetings index page, without changing the default filters, "Export calendar" button will open a pop-up with a general link.

On the same page, after changing one ore more filters, the button is not working.

To Reproduce
Steps to reproduce the behavior:

1. Go to meetings index page
2. Change default filters
3. Click on 'Export calendar' button
4. Noting happens

Expected behavior
On meetings index page, when changing one ore more filters, "Export calendar" button should display the correct link, based on the section made.

Screenshots
If applicable, add screenshots to help explain your problem.

Stacktrace
If applicable, add the error stacktrace to help explain your problem.

Extra data (please complete the following information):

• Device: [e.g. iPhone6, Desktop]
• Device OS: [e.g. iOS8.1, Windows 10]
• Browser: [e.g. Chrome, Firefox, Safari]
• Decidim Version: [e.g. 0.10]
• Decidim installation: [e.g. MetaDecidim]

Additional context
Add any other context about the problem here. For instance, add Metadecidim link.