Auto merge of #13068 - ashrko619:shut_down_layout_panic, r=jdm

Fixed calling unwrap on an Err value

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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #13046  (github issue number if applicable).

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components/script/script_thread.rs

@@ -2201,7 +2201,7 @@ fn shut_down_layout(context_tree: &BrowsingContext) {
         let chan = window.layout_chan().clone();
         if chan.send(message::Msg::PrepareToExit(response_chan)).is_ok() {
             channels.push(chan);
-            response_port.recv().unwrap();
+            let _ = response_port.recv();
         }
     }