cleanup delegate test

Author: yinyiqian1

src/test/app/Delegate_test.cpp

@@ -706,19 +706,16 @@ class Delegate_test : public beast::unit_test::suite
             Account const bob{"bob"};
             Account const gw{"gateway"};
             Account const carol{"carol"};
-            Account const dan{"dan"};
             auto const USD = gw["USD"];
 
-            env.fund(XRP(10000), alice, bob, carol, dan, gw);
+            env.fund(XRP(10000), alice, bob, carol, gw);
             env.close();
             env.trust(USD(50000), alice);
             env.trust(USD(50000), bob);
             env.trust(USD(50000), carol);
-            env.trust(USD(50000), dan);
             env(pay(gw, alice, USD(10000)));
             env(pay(gw, bob, USD(10000)));
             env(pay(gw, carol, USD(10000)));
-            env(pay(gw, dan, USD(10000)));
             env.close();
 
             // PaymentMint