Fix notices in phpunit

phpunit.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<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/11.2/phpunit.xsd" cacheDirectory=".phpunit.cache" backupStaticProperties="false">
+<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/11.2/phpunit.xsd">
   <testsuites>
     <testsuite name="Feature">
       <directory suffix="Test.php">./tests/Feature</directory>
@@ -16,9 +16,9 @@
     <env name="QUEUE_DRIVER" value="sync"/>
     <env name="APP_KEY" value="value_from_phpunit"/>
   </php>
-  <source>
+  <coverage>
     <include>
       <directory suffix=".php">./app</directory>
     </include>
-  </source>
+  </coverage>
 </phpunit>

tests/Feature/ConversationChangeCustomerTest.php

@@ -71,6 +71,7 @@ class ConversationChangeCustomerTest extends TestCase
      * This is the regression test for the authorization bypass where changeCustomer()
      * executed unconditionally even when permission checks set an error message.
      */
+    #[RequiresPhp('>=8.3.0')]
     public function testUnauthorizedUserCannotChangeCustomer()
     {
         $response = $this->actingAs($this->unprivUser)
@@ -98,6 +99,7 @@ class ConversationChangeCustomerTest extends TestCase
      * Test that an authorized admin user CAN change a conversation's customer.
      * This ensures the fix does not break normal functionality.
      */
+    #[RequiresPhp('>=8.3.0')]
     public function testAuthorizedUserCanChangeCustomer()
     {
         $response = $this->actingAs($this->admin)