Mark panic::ExtraInfo as non-exhaustive.

Co-authored-by: Mara Bos <m-ou.se@m-ou.se>

Author: 2 people

library/core/src/panic/extra_info.rs

@@ -1,6 +1,7 @@
 use crate::panic::assert_info::AssertInfo;
 
 #[derive(Debug, Copy, Clone)]
+#[non_exhaustive]
 pub enum ExtraInfo<'a> {
     AssertInfo(&'a AssertInfo<'a>),
 }