Fix emoji rendering in collapsed sidebar labels (#8113)

* Initial plan

* Fix: Use displayName for label emojis in compact view

Co-authored-by: alexr00 <38270282+alexr00@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: alexr00 <38270282+alexr00@users.noreply.github.com>

Author: Copilot

webviews/components/sidebar.tsx

@@ -383,7 +383,7 @@ function CollapsedLabel(props: PullRequest) {
 					items={labels}
 					getKey={l => l.name}
 					getColor={l => gitHubLabelColor(l.color, props?.isDarkTheme, false)}
-					getText={l => l.name}
+					getText={l => l.displayName}
 				/>
 			),
 			count: labels.length