Warning: require(vendor/autoload.php): Failed to open stream: No such file or directory in C:\xampp\htdocs\astra-backoffice\vendor\masterminds\html5\example.php on line 3

Fatal error: Uncaught Error: Failed opening required 'vendor/autoload.php' (include_path='C:\xampp\php\PEAR') in C:\xampp\htdocs\astra-backoffice\vendor\masterminds\html5\example.php:3 Stack trace: #0 {main} thrown in C:\xampp\htdocs\astra-backoffice\vendor\masterminds\html5\example.php on line 3