Added Constructor to Administration Class

src/main/java/org/example/Administration.java

@@ -7,7 +7,11 @@ public class Administration {
     private List<Professor> professors;
     private List<Admin> admins;
 
-
+    public Administration()
+    {
+        this.professors = new ArrayList<>();
+        this.admins = new ArrayList<>();
+    }
 
 
 }