Fix a failing test case

Author: weiznich

diesel_tests/tests/update.rs

@@ -233,7 +233,7 @@ fn upsert_with_no_changes_executes_do_nothing() {
     struct Changes {
         hair_color: Option<String>,
     }
-
+    {
     let connection = connection_with_sean_and_tess_in_users_table();
     let result = insert_into(users::table)
         .values(&User::new(1, "Sean"))
@@ -243,7 +243,9 @@ fn upsert_with_no_changes_executes_do_nothing() {
         .execute(&connection);
 
     assert_eq!(Ok(0), result);
+    }
 
+    {
     // Try the same thing with an owned type.
     let connection = connection_with_sean_and_tess_in_users_table();
     let result = insert_into(users::table)
@@ -254,6 +256,7 @@ fn upsert_with_no_changes_executes_do_nothing() {
         .execute(&connection);
 
     assert_eq!(Ok(0), result);
+    }
 }
 
 #[test]