Remove sidebar when conference has no components

[ElviaBth]

🎩 What? Why?

Although there is nothing in the submenu of the participatory space, the sidebar appears.
Nothing should be displayed if there is no sub-menu section.

To fix this a conditional render was added so if there are any conference_nav_items, then layout_two_col will be displayed in another case layout_center.

📌 Related Issues

• Related to #
• Fixes #?

Testing

• Go to Decidim
• Sign in at http://localhost:3000
• Visit conferences
• Create a new conference(don't add any component) and publish.
• See the site, there is an empty sidebar.

📷 Screenshots

before

after

♥️ Thank you!

[request-info]

It seems like you did not give us much information about what you are trying to do here. We would appreciate it if you could provide us with more info about this issue/PR!

[github-actions]

This pull request does not contain a valid label. Please add one of the following labels: ['type: feature', 'type: change', 'type: fix', 'type: removal', 'target: developer-experience', 'type: internal']

[andreslucena]

@carolromero should we show no sidebar (as in the screenshot) or empty sidebar (without the empty purple box of course)?

[carolromero]

@andreslucena better not to show the sidebar as @ElviaBth suggests in the PR.

[andreslucena]

I tried it locally, and it works as expected, also the tests are perfect! 👏🏽 👏🏽

I'd like to change the tertiary operator to give it a variable and not have too much noise in the same line. It's just a stylistic thing.

[andreslucena]

👍🏽