Decidim: Error on proposals relations with meetings

[josanFFiG]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behaviour:

1. Click '🔒 Close' through administration options on a concrete meeting
2. Scroll down to 'Proposals' (select proposals), do not full-field any other field
3. Search for proposals you want to link to this meeting and mark them
4. Click blue button 'Close'.
5. System will return you an error, marking in red empty mandatory fields for closing (all except first one 'Report' that will not be shown marked on red).
6. Full-field the empty fields marked as an error, do not full-field "Report" one.
7. Click blue button 'Close'.
8. A new error message will be shown and marked in red: "Report" field is empty.
9. Now have a look on proposals linked to the meeting: every single proposal on participatory space have suddenly been linked to the meeting.

Expected behavior
Once you have selected the related proposals these should not change even if there are errors on closing.

Screenshots

Related issues
Improve UI for Proposals relations with Meetings #5717
https://github.com/decidim/decidim/issues/5717
https://github.com/decidim/decidim/pull/5863
ref: ref: PP040

Extra data (please complete the following information):

• Device: Desktop
• Device OS: Ubuntu
• Browser: Firefox
• Decidim Version: 0.22
• Decidim installation: preprod.decidim.barcelona

[marinavega]

@decidim/product @josanFFiG The fix can be tested here 😃

[carolromero]

@marinavega this is working ok now, thanks! @josanFFiG take a look if you can :relaxed:

[josanFFiG]

GREAT!