Updated test configuration

.gitignore

@@ -1,4 +1,5 @@
 /.idea/
 /vendor/
 .phpunit.result.cache
-composer.lock
+.phpunit.cache
+composer.lock

phpunit.xml.dist

@@ -1,21 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<phpunit backupGlobals="false"
-         backupStaticAttributes="false"
-         bootstrap="vendor/autoload.php"
-         colors="true"
-         convertDeprecationsToExceptions="true"
-         convertErrorsToExceptions="true"
-         convertNoticesToExceptions="true"
-         convertWarningsToExceptions="true"
-         processIsolation="false"
-         stopOnFailure="false"
->
-    <testsuites>
-        <testsuite name="Ladder Test Suite">
-            <directory suffix=".php">./tests/</directory>
-        </testsuite>
-    </testsuites>
-    <php>
-        <server name="APP_KEY" value="yqTzObeFpDe5NHTCEwdu17j2fTcbbALQ"/>
-    </php>
-</phpunit>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" backupGlobals="false" bootstrap="vendor/autoload.php" colors="true" processIsolation="false" stopOnFailure="false" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/11.0/phpunit.xsd" cacheDirectory=".phpunit.cache" backupStaticProperties="false">
+  <testsuites>
+    <testsuite name="Ladder Test Suite">
+      <directory suffix="Test.php">./tests/</directory>
+    </testsuite>
+  </testsuites>
+  <php>
+    <server name="APP_KEY" value="yqTzObeFpDe5NHTCEwdu17j2fTcbbALQ"/>
+  </php>
+</phpunit>