fix: don't use davtags for tag search

1. https://github.com/nextcloud/server/pull/26813 Initial implementation with support for systemtags and davtags (vcategory)
2. https://github.com/nextcloud/server/pull/39062 Additional check if the given tag exists, though ISystemTagManager.getAllTags only looks for systemtags

Therefore it's not possible anymore to search for davtags and unnecessary to join the other tables.

Signed-off-by: Daniel Kesselberg <mail@danielkesselberg.de>

apps/systemtags/lib/Search/TagSearchProvider.php

@@ -120,10 +120,7 @@ class TagSearchProvider implements IProvider {
 
 		$userFolder = $this->rootFolder->getUserFolder($user->getUID());
 		$fileQuery = new SearchQuery(
-			new SearchBinaryOperator(SearchBinaryOperator::OPERATOR_OR, [
-				new SearchComparison(ISearchComparison::COMPARE_LIKE, 'tagname', '%' . $query->getTerm() . '%'),
-				new SearchComparison(ISearchComparison::COMPARE_LIKE, 'systemtag', '%' . $query->getTerm() . '%'),
-			]),
+			new SearchComparison(ISearchComparison::COMPARE_LIKE, 'systemtag', '%' . $query->getTerm() . '%'),
 			$query->getLimit(),
 			(int)$query->getCursor(),
 			$query->getSortOrder() === ISearchQuery::SORT_DATE_DESC ? [