OZG-6798 remove redundant test

nachrichten-manager-server/src/test/java/de/ozgcloud/nachrichten/email/MailSendRequestValidationTest.java

@@ -29,26 +29,6 @@ class MailSendRequestValidationTest {
 			assertThat(violations).isEmpty();
 		}
 
-		@Test
-		void shouldBeInvalidOnNull() {
-			var ds = new ByteArrayDataSource(ATTACHMENT.getBytes(), "plain/text");
-			ds.setName(ATTACHMENT_NAME);
-			var request = MailSendRequest.builder()
-					.fromAddress(FROM)
-					.subject(SUBJECT)
-					.body(BODY)
-					.requestReference(REFERENCE)
-					.attachment(MailAttachment.builder()
-							.dataSource(ds)
-							.build())
-					.replyTo(REPLY_TO)
-					.build();
-
-			var violations = validator.validate(request);
-
-			assertThat(violations).isNotEmpty();
-		}
-
 		@Test
 		void shouldBeInvalidOnEmpty() {
 			var request = MailSendRequestTestFactory.createBuilder().clearToAddresses().build();