Update PHPUnit config (#613)

Author: Brian Faust

phpunit.xml

@@ -1,10 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.0/phpunit.xsd" backupGlobals="false" bootstrap="vendor/autoload.php" colors="true" processIsolation="false" stopOnFailure="false" cacheDirectory=".phpunit.cache" backupStaticProperties="false">
-  <coverage>
-    <include>
-      <directory suffix=".php">./src</directory>
-    </include>
-  </coverage>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.1/phpunit.xsd" backupGlobals="false" bootstrap="vendor/autoload.php" colors="true" processIsolation="false" stopOnFailure="false" cacheDirectory=".phpunit.cache" backupStaticProperties="false">
+  <coverage/>
   <testsuites>
     <testsuite name="Unit">
       <directory suffix="Test.php">./tests/Unit</directory>
@@ -13,4 +9,9 @@
       <directory suffix="Test.php">./tests/Feature</directory>
     </testsuite>
   </testsuites>
+  <source>
+    <include>
+      <directory suffix=".php">./src</directory>
+    </include>
+  </source>
 </phpunit>