Update PHPUnit schema

Author: rbibby

phpunit.xml.dist

@@ -1,20 +1,13 @@
-<phpunit
-    bootstrap="./vendor/autoload.php"
-    colors="true"
-    verbose="true"
-    convertErrorsToExceptions="true"
-    convertNoticesToExceptions="true"
-    convertWarningsToExceptions="true"
-    >
-    <testsuites>
-        <testsuite name="Unit Tests">
-            <directory suffix="Test.php">./tests</directory>
-        </testsuite>
-    </testsuites>
-
-    <filter>
-        <whitelist processUncoveredFilesFromWhitelist="true">
-            <directory suffix=".php">./src</directory>
-        </whitelist>
-    </filter>
+<?xml version="1.0"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" bootstrap="./vendor/autoload.php" colors="true" verbose="true" convertErrorsToExceptions="true" convertNoticesToExceptions="true" convertWarningsToExceptions="true" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd">
+  <coverage processUncoveredFiles="true">
+    <include>
+      <directory suffix=".php">./src</directory>
+    </include>
+  </coverage>
+  <testsuites>
+    <testsuite name="Unit Tests">
+      <directory suffix="Test.php">./tests</directory>
+    </testsuite>
+  </testsuites>
 </phpunit>