Update ui test suite to nightly-2021-05-14

test_suite/tests/ui/remote/wrong_de.stderr

@@ -7,4 +7,4 @@ error[E0308]: mismatched types
   |          expected `u16`, found `u8`
   |          help: you can convert a `u8` to a `u16`: `Deserialize.into()`
   |
-  = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
+  = note: this error originates in the derive macro `Deserialize` (in Nightly builds, run with -Z macro-backtrace for more info)

test_suite/tests/ui/remote/wrong_getter.stderr

@@ -6,4 +6,4 @@ error[E0308]: mismatched types
    |
    = note: expected reference `&u8`
               found reference `&u16`
-   = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
+   = note: this error originates in the derive macro `Serialize` (in Nightly builds, run with -Z macro-backtrace for more info)

test_suite/tests/ui/remote/wrong_ser.stderr

@@ -6,4 +6,4 @@ error[E0308]: mismatched types
   |
   = note: expected reference `&u8`
              found reference `&u16`
-  = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
+  = note: this error originates in the derive macro `Serialize` (in Nightly builds, run with -Z macro-backtrace for more info)

test_suite/tests/ui/struct-representation/internally-tagged-unit.stderr

@@ -4,4 +4,4 @@ error: #[serde(tag = "...")] can only be used on enums and structs with named fi
 3 | #[derive(Serialize)]
   |          ^^^^^^^^^
   |
-  = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
+  = note: this error originates in the derive macro `Serialize` (in Nightly builds, run with -Z macro-backtrace for more info)