fix(mail): pin down HTTP Port in TC test for MailServiceBeanIT IQSS#11472

Without pinning down the port, sometimes Testcontainers thinks it should
apply the waiting strategy on the SMTP port. Telling it explicitely
which port to use fixes this.

Author: poikilotherm

src/test/java/edu/harvard/iq/dataverse/MailServiceBeanIT.java

@@ -75,7 +75,7 @@ static void setUp() {
     @Container
     static GenericContainer<?> maildev = new GenericContainer<>("dockage/mailcatcher")
         .withExposedPorts(PORT_HTTP, PORT_SMTP)
-        .waitingFor(Wait.forHttp("/"));
+        .waitingFor(Wait.forHttp("/").forPort(PORT_HTTP));
 
     static String tcSmtpHost() {
         return maildev.getHost();