Fix

Author: sebastianbergmann

tests/_files/phpunit-example-extension/phpunit.xml

@@ -1,6 +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/5.7/phpunit.xsd"
+         xsi:noNamespaceSchemaLocation="../../../phpunit.xsd"
          verbose="true"
          extensionsDirectory="tools/phpunit.d">
     <testsuite name="default">

tests/end-to-end/loggers/_files/hooks.xml

@@ -1,6 +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/7.1/phpunit.xsd"
+         xsi:noNamespaceSchemaLocation="../../../../phpunit.xsd"
          printerClass="PHPUnit\Test\NullPrinter">
     <extensions>
         <extension class="PHPUnit\Test\Extension">

tests/end-to-end/regression/GitHub/3379/phpunit.xml

@@ -1,6 +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/7.4/phpunit.xsd">
+         xsi:noNamespaceSchemaLocation="../../../../../phpunit.xsd">
     <testsuites>
         <testsuite name="default">
             <directory suffix="Test.php">.</directory>