Update PHPUnit configuration

Author: sebastianbergmann

phpunit.xml

@@ -5,14 +5,18 @@
          cacheDirectory=".phpunit.cache"
          executionOrder="depends,defects"
          beStrictAboutOutputDuringTests="true"
+         displayDetailsOnPhpunitDeprecations="true"
+         failOnPhpunitDeprecation="true"
+         failOnRisky="true"
+         failOnWarning="true"
          colors="true">
     <testsuites>
         <testsuite name="default">
             <directory>tests/tests</directory>
         </testsuite>
     </testsuites>
 
-    <source>
+    <source restrictDeprecations="true" restrictNotices="true" restrictWarnings="true">
         <include>
             <directory>src</directory>
         </include>