MDL-81456 core: Correct namespace imports

lib/phpunit/classes/advanced_testcase.php

@@ -14,10 +14,8 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
 
-use core\{
-    di,
-    hook,
-};
+use core\di;
+use core\hook;
 
 /**
  * Advanced PHPUnit test case customised for Moodle.

lib/phpunit/classes/util.php

@@ -23,10 +23,8 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
-use core\{
-    di,
-    hook,
-};
+use core\di;
+use core\hook;
 
 require_once(__DIR__.'/../../testing/classes/util.php');
 require_once(__DIR__ . "/coverage_info.php");