Add '--skip-update-check' flag to plugin and theme list command

By default WP-CLI does a force update check when running 'wp plugin list' and 'wp theme list'
'--skip-update-check' flag can be added to these commands which can bypass the force udpate check

Author: Nikschavan

src/Plugin_Command.php

@@ -1082,6 +1082,9 @@ public function delete( $args, $assoc_args = array() ) {
 	 *   - inactive
 	 *   - must-use
 	 * ---
+	 * 
+	 * [--skip-update-check]
+	 * : If set, the plugin update check will be skipped.
 	 *
 	 * ## AVAILABLE FIELDS
 	 *

src/Theme_Command.php

@@ -831,6 +831,9 @@ public function delete( $args, $assoc_args ) {
 	 *   - parent
 	 *   - inactive
 	 * ---
+	 * 
+	 * [--skip-update-check]
+	 * : If set, the plugin update check will be skipped.
 	 *
 	 * ## AVAILABLE FIELDS
 	 *

src/WP_CLI/CommandWithUpgrade.php

@@ -480,8 +480,11 @@ static function ( $result ) {
 
 	// phpcs:ignore PSR2.Methods.MethodDeclaration.Underscore -- Whitelisting to provide backward compatibility to classes possibly extending this class.
 	protected function _list( $_, $assoc_args ) {
-		// Force WordPress to check for updates
-		call_user_func( $this->upgrade_refresh );
+
+		// Force WordPress to check for updates if `--skip-update-check` is not passed.
+		if ( empty( $assoc_args['skip-update-check'] ) ) {
+			call_user_func( $this->upgrade_refresh );
+		}
 
 		$all_items = $this->get_all_items();