Allow admins to see a participant's email from their profile page

This feature is building on this one: https://github.com/decidim/decidim/issues/5722 In the following PR (https://github.com/decidim/decidim/pull/5849), the possibility for an admin to see a participant's e-mail has been added to the participants list in the admin panel. I am suggesting to add the exact same button to the profile page of the user, next to the currently existing button to send a private message (see screenshot). This button would trigger the exact same behaviour (popup with a button to "show" the address and would of course log the action in the same way. The reasoning behind this suggestion is that the admin using our platforms often work from the content (proposals, initiatives...) and then might need to contact its author (for clarifications, etc...). When they do so, it is better to give them access to the e-mail in a context-based way rather than forcing them to copy the user's name, going to the admin panel, searching for the right user (potentially mistakenly picking the wrong one) and pressing the button. Finally, I would add that this is C