Auto merge of #12175 - andrebeat:fix-handle-cmd-unwrap, r=ConnorGBrewster

Remove unnecessary uses of unwrap in ImageCache::handle_cmd

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Remove unnecessary uses of unwrap in `ImageCache::handle_cmd`.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12173

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- [X] These changes do not require tests

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components/net/image_cache_thread.rs

@@ -406,11 +406,11 @@ impl ImageCache {
             }
             ImageCacheCommand::GetImageIfAvailable(url, use_placeholder, consumer) => {
                 let result = self.get_image_if_available(url, use_placeholder);
-                consumer.send(result).unwrap();
+                let _ = consumer.send(result);
             }
             ImageCacheCommand::GetImageOrMetadataIfAvailable(url, use_placeholder, consumer) => {
                 let result = self.get_image_or_meta_if_available(url, use_placeholder);
-                consumer.send(result).unwrap();
+                let _ = consumer.send(result);
             }
             ImageCacheCommand::StoreDecodeImage(url, image_vector) => {
                 self.store_decode_image(url, image_vector);