Fix extensions checking

Author: RobiNN1

src/Admin.php

@@ -30,9 +30,8 @@ class Admin {
      */
     public function __construct(?Template $template = null) {
         foreach (Config::get('dashboards') as $class) {
-            $dashboard = new $class($template);
-
-            if ($dashboard instanceof DashboardInterface && $dashboard->check()) {
+            if (is_subclass_of($class, DashboardInterface::class) && $class::check()) {
+                $dashboard = new $class($template);
                 $info = $dashboard->getDashboardInfo();
                 $this->dashboards[$info['key']] = $dashboard;
             }

src/Dashboards/APCu/APCuDashboard.php

@@ -30,7 +30,7 @@ public function __construct(Template $template) {
      *
      * @return bool
      */
-    public function check(): bool {
+    public static function check(): bool {
         return extension_loaded('apcu');
     }
 

src/Dashboards/DashboardInterface.php

@@ -18,7 +18,7 @@ interface DashboardInterface {
      *
      * @return bool
      */
-    public function check(): bool;
+    public static function check(): bool;
 
     /**
      * Get dashboard info.

src/Dashboards/Memcached/MemcachedDashboard.php

@@ -38,7 +38,7 @@ public function __construct(Template $template) {
      *
      * @return bool
      */
-    public function check(): bool {
+    public static function check(): bool {
         return extension_loaded('memcache') || extension_loaded('memcached');
     }
 

src/Dashboards/OPCache/OPCacheDashboard.php

@@ -31,7 +31,7 @@ public function __construct(Template $template) {
      *
      * @return bool
      */
-    public function check(): bool {
+    public static function check(): bool {
         return extension_loaded('Zend OPcache');
     }
 

src/Dashboards/Redis/RedisDashboard.php

@@ -43,7 +43,7 @@ public function __construct(Template $template) {
      *
      * @return bool
      */
-    public function check(): bool {
+    public static function check(): bool {
         return extension_loaded('redis');
     }
 

src/Dashboards/Server/ServerDashboard.php

@@ -30,7 +30,7 @@ public function __construct(Template $template) {
      *
      * @return bool
      */
-    public function check(): bool {
+    public static function check(): bool {
         return true; // No extension required, just return true.
     }