Fix missing usages of MessageTransformer for Throwable sanitization

src/main/java/de/tum/in/test/api/internal/sanitization/MultipleFailuresErrorSanitizer.java

@@ -30,7 +30,7 @@ public Throwable sanitize(Throwable t, MessageTransformer messageTransformer) {
 		 * So we just pass the message constructed be the old object, as the new object
 		 * will in absence of failures only return the heading.
 		 */
-		MultipleFailuresError newMfe = createNewInstance(mfe, info.getMessage(), List.of());
+		MultipleFailuresError newMfe = createNewInstance(mfe, messageTransformer.apply(info), List.of());
 		SanitizationUtils.copyThrowableInfoSafe(info, newMfe);
 		// Retain failure information in the suppressed Throwables
 		for (Throwable failure : failures)

src/main/java/de/tum/in/test/api/internal/sanitization/SafeTypeThrowableSanitizer.java

@@ -68,6 +68,7 @@ public Throwable sanitize(Throwable t, MessageTransformer messageTransformer) {
 		// this is OK because we are only dealing with safe types here
 		ThrowableInfo info = ThrowableInfo.of(type, ThrowableUtils.retrievePropertyValues(t));
 		info.sanitize(ThrowableUtils.PROPERTY_SANITIZER);
+		info.setMessage(messageTransformer.apply(info));
 		var throwableCreator = cachedThrowableCreators.computeIfAbsent(type, this::findThrowableCreator);
 		try {
 			Throwable newInstance = throwableCreator.create(info);