Elide lifetimes where possible after rustup (#34824)

The new version of rust allows us to elide some lifetimes and clippy is
now complaining about this. This change elides them where possible and
removes the clippy exceptions.

Fixes #34804.

Signed-off-by: Martin Robinson <mrobinson@igalia.com>

components/script/realms.rs

@@ -33,7 +33,7 @@ pub enum InRealm<'a> {
     Entered(&'a JSAutoRealm),
 }
 
-impl<'a> InRealm<'a> {
+impl InRealm<'_> {
     pub fn already(token: &AlreadyInRealm) -> InRealm {
         InRealm::Already(token)
     }