Fix 'elided lifetime' warning from nightly

Nightly 1.90. The fix passes on stable 1.88.

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

tokio-xmpp/ChangeLog

@@ -47,6 +47,7 @@ XXXX-YY-ZZ RELEASER <admin@example.com>
         on the `tls-rust-ktls` feature. (!458, !490)
       - Building with insecure-tcp and no other feature got fixed.
       - Update rxml dependency to 0.13.
+      - Remove warnings for elided lifetimes (rustc 1.90)
 
 Version 4.0.0:
 2024-07-26 Maxime “pep” Buquet <pep@bouah.net>

tokio-xmpp/src/stanzastream/worker.rs

@@ -334,7 +334,7 @@ impl WorkerStream {
         }
     }
 
-    fn close(&mut self) -> Close {
+    fn close(&mut self) -> Close<'_> {
         Close {
             stream: Pin::new(self),
         }