[TASK] Clean up the unit tests configuration (#1389)

Remove no longer needed bootstrap option.
Remove no longer needed backupGlobals options.

Resolves: #1347

Build/phpunit/UnitTests.xml

@@ -2,9 +2,7 @@
 <phpunit
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.6/phpunit.xsd"
-    backupGlobals="true"
     beStrictAboutTestsThatDoNotTestAnything="false"
-    bootstrap="../../.Build/vendor/typo3/testing-framework/Resources/Core/Build/UnitTestsBootstrap.php"
     cacheResult="false"
     colors="true"
     controlGarbageCollector="true"