N°6934 - Symfony 6.4 - upgrade Symfony bundles to 6.4 (#580)

* Update Symfony lib to version ~6.4.0
* Update code missing return type
* Add an iTop general configuration entry to store application secret (Symfony mandatory parameter)
* Use dependency injection in ExceptionListener & UserProvider classes

lib/symfony/web-profiler-bundle/Resources/views/Icon/mailer.svg

@@ -1 +1,6 @@
-<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24"><path fill="#AAAAAA" d="M22,4.9C22,3.9,21.1,3,20.1,3H3.9C2.9,3,2,3.9,2,4.9v13.1C2,19.1,2.9,20,3.9,20h16.1c1.1,0,1.9-0.9,1.9-1.9V4.9z M8.3,14.1l-3.1,3.1c-0.2,0.2-0.5,0.3-0.7,0.3S4,17.4,3.8,17.2c-0.4-0.4-0.4-1,0-1.4l3.1-3.1c0.4-0.4,1-0.4,1.4,0S8.7,13.7,8.3,14.1z M20.4,17.2c-0.2,0.2-0.5,0.3-0.7,0.3s-0.5-0.1-0.7-0.3l-3.1-3.1c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l3.1,3.1C20.8,16.2,20.8,16.8,20.4,17.2z M20.4,7.2l-7.6,7.6c-0.2,0.2-0.5,0.3-0.7,0.3s-0.5-0.1-0.7-0.3L3.8,7.2c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l6.9,6.9L19,5.8c0.4-0.4,1-0.4,1.4,0S20.8,6.8,20.4,7.2z"/></svg>
+<svg xmlns="http://www.w3.org/2000/svg" data-icon-name="icon-tabler-mail" width="24" height="24" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor" fill="none" stroke-linecap="round" stroke-linejoin="round">
+    <path stroke="none" d="M0 0h24v24H0z" fill="none"></path>
+    <rect x="3" y="5" width="18" height="14" rx="2"></rect>
+    <polyline points="3 7 12 13 21 7"></polyline>
+</svg>
+