Update ui tests to 2018 edition

test_suite/tests/ui/remote/enum_getter.stderr

@@ -1,13 +1,13 @@
 error: #[serde(getter = "...")] is not allowed in an enum
-  --> $DIR/enum_getter.rs:11:1
+  --> $DIR/enum_getter.rs:10:1
    |
-11 | / #[serde(remote = "remote::E")]
-12 | | pub enum E {
-13 | |     A {
-14 | |         #[serde(getter = "get_a")]
-15 | |         a: u8,
-16 | |     },
-17 | | }
+10 | / #[serde(remote = "remote::E")]
+11 | | pub enum E {
+12 | |     A {
+13 | |         #[serde(getter = "get_a")]
+14 | |         a: u8,
+15 | |     },
+16 | | }
    | |_^
 
 error: aborting due to previous error