Revert "Move cache read inside VarDumper handler to avoid cache call …

…during package discovery/composer install calls (#1025)" (#1030)

This reverts commit 897d2e0.

src/Watchers/DumpWatcher.php

@@ -40,14 +40,14 @@ public function __construct(CacheFactory $cache, array $options = [])
      */
     public function register($app)
     {
+        if (! $this->cache->get('telescope:dump-watcher')) {
+            return;
+        }
+
         $htmlDumper = new HtmlDumper();
         $htmlDumper->setDumpHeader('');
 
         VarDumper::setHandler(function ($var) use ($htmlDumper) {
-            if (! $this->cache->get('telescope:dump-watcher')) {
-                return;
-            }
-
             $this->recordDump($htmlDumper->dump(
                 (new VarCloner)->cloneVar($var), true
             ));