tests: harden the config

Author: williamdes

phpunit.xml

@@ -3,6 +3,10 @@
         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/7.0/phpunit.xsd"
         colors="true"
         backupGlobals="false"
+        beStrictAboutOutputDuringTests="true"
+        convertErrorsToExceptions="true"
+        convertNoticesToExceptions="true"
+        convertWarningsToExceptions="true"
         bootstrap="vendor/autoload.php"
 >