Show that user search is in progress #10531

[fgsl]

• During the processing of the research, there is no indication that the research is being processed.
• For a backend with thousands of users, this can generate doubts to user about the processing.

[ChristophWurst]

I'm very sorry that nobody noticed this PR.

I checked the existing code and that already updates the UI accordingly during the search:

server/core/js/contactsmenu.js

Lines 517 to 523 in c58188f

	if (_.isUndefined(searchTerm) || searchTerm === '') {
	self._view.showLoading(t('core', 'Loading your contacts …'));
	} else {
	self._view.showLoading(t('core', 'Looking for {term} …', {
	term: searchTerm
	}));
	}

.

Therefore I'm closing this pull request.