Add support for the SignalConso experiment

[teolemon]

Problem

• Add support for the SignalConso experiment
• We got the URLs to create a knowledge panels with a button, as well as their target mockups (we also have our own)
• You can see it in production: https://signal.conso.gouv.fr/fr/alimentaire-codebarres/faire-un-signalement?gtin=3017620422003
• The URL is always the same: https://signal.conso.gouv.fr/fr/alimentaire-codebarres/faire-un-signalement?gtin=LE_CODE_BARRES_ICI
• This URL is made especially for you. It cannot be discovered by browsing the site.
• "It is now up to you to build this link on your product sheets, if possible following the model that I suggested" https://excalidraw.com/#json=JVKcZOSmxXzWiZnRSAvcO,7wdyPlzRZT2fTjaeMqkuVQ

Part of

• #Product page

[stephanegigandet]

@teolemon Can you add the details in the bug, or link to related docs?

[teolemon]

done @stephanegigandet

[stephanegigandet]

Done in #10106