Do not send (practically) empty reports

core/src/main/java/nl/tudelft/ewi/auta/core/controller/SubmitAppController.java

@@ -275,7 +275,7 @@ public class SubmitAppController extends ControllerBase
                 try {
                     final var report = this.reportGenerator.generateReport(
                             entityContainer, Set.of(e.getKey())
-                    );
+                    ).trim();
 
                     this.sendFeedback(url, report, e.getValue(), submitMetadata, null, true);
                 } catch (final IOException | TemplateException ex) {
@@ -316,6 +316,8 @@ public class SubmitAppController extends ControllerBase
     /**
      * Sends a report to Submit.
      *
+     * If the report is empty, this does nothing.
+     *
      * @param url the URL to send the feedback to
      * @param report the report to send
      * @param visibleFor for whom the report should be visible
@@ -332,6 +334,10 @@ public class SubmitAppController extends ControllerBase
             final @Nullable Integer score,
             final boolean success
     ) {
+        if (report != null && report.isEmpty()) {
+            return;
+        }
+
         try {
             final var conn = (HttpURLConnection) url.openConnection();
             conn.setDoOutput(true);