fix sample form twig submit action url

src/Views/sample_form.html.twig

@@ -8,7 +8,7 @@
 
 <h1>Hello, this is a sample form made in Twig !</h1>
 
-<form action="/submit-twig" method="POST">
+<form action="submit-twig" method="POST">
     <label for="name">your name: </label>
     <input type="text" id="name" name="name"/>
     <label for="password">a little description about yourself: </label>