feat(mail) : install webklex/php-imap + symfony/lock, configure lock store

phpunit.dist.xml

@@ -16,6 +16,12 @@
         <server name="APP_ENV" value="test" force="true" />
         <server name="SHELL_VERBOSITY" value="-1" />
         <server name="KERNEL_CLASS" value="App\Kernel" />
+
+        <!-- ###+ symfony/lock ### -->
+        <!-- Choose one of the stores below -->
+        <!-- postgresql+advisory://db_user:db_password@localhost/db_name -->
+        <env name="LOCK_DSN" value="flock"/>
+        <!-- ###- symfony/lock ### -->
     </php>
 
     <testsuites>