Fix problem with threads without replies

view/src/main/java/se/su/dsv/scipro/forum/panels/threaded/ProjectForumThread.java

@@ -24,6 +24,9 @@ public class ProjectForumThread implements ForumThread<ProjectThread> {
     @Override
     public List<ForumPost> getReplies(final ProjectThread projectThread) {
         List<ForumPost> posts = projectForumService.getPosts(projectThread);
+        if (posts.size() <= 1) {
+            return List.of();
+        }
         return posts.subList(1, posts.size());
     }
 

view/src/main/java/se/su/dsv/scipro/group/GroupForumThread.java

@@ -24,6 +24,9 @@ public class GroupForumThread implements ForumThread<GroupThread> {
     @Override
     public List<ForumPost> getReplies(final GroupThread groupThread) {
         List<ForumPost> posts = groupForumService.getPosts(groupThread);
+        if (posts.size() <= 1) {
+            return List.of();
+        }
         return posts.subList(1, posts.size());
     }