update fallback purchase url

Author: JurriaanK

src/shared/class-hub-page.php

@@ -423,7 +423,7 @@ class="gwp-btn gwp-btn--icon gwp-btn--danger gwp-btn--sm gwp-hub-action"
 		private static function render_locked_footer( $plugin, $slug ) {
 			$purchase_url = ! empty( $plugin['purchase_url'] )
 				? $plugin['purchase_url']
-				: 'https://gravitywp.com/pricing/?utm_source=hub&utm_medium=admin&utm_campaign=upgrade&utm_content=' . rawurlencode( $slug );
+				: 'https://gravitywp.com/add-ons/?utm_source=hub&utm_medium=admin&utm_campaign=upgrade&utm_content=' . rawurlencode( $slug );
 			$is_free      = ! empty( $plugin['is_free'] );
 
 			ob_start();