fix: typo in log message

Co-authored-by: John Paul E. Balandan, CPA <51850998+paulbalandan@users.noreply.github.com>

Author: kenjis

system/Debug/Toolbar.php

@@ -55,8 +55,8 @@ public function __construct(ToolbarConfig $config)
             if (! class_exists($collector)) {
                 log_message(
                     'critical',
-                    'Toolbar collector does not exists(' . $collector . ').'
-                    . ' please check $collectors in the app/Config/Toolbar.php file.'
+                    'Toolbar collector does not exist (' . $collector . ').'
+                    . ' Please check $collectors in the app/Config/Toolbar.php file.'
                 );
 
                 continue;