feat(ui): update TrendingVideos dismiss button style

Changed the TrendingVideos dismiss button to use solid variant and
square shape for improved visibility. Also set ButtonIcon size to "sm"
for better alignment with the new button style.

src/components/interstitials/TrendingVideos.tsx

@@ -89,11 +89,11 @@ export function TrendingVideos() {
         <Button
           label={_(msg`Dismiss this section`)}
           size="tiny"
-          variant="ghost"
+          variant="solid"
           color="secondary"
-          shape="round"
+          shape="square"
           onPress={() => trendingPrompt.open()}>
-          <ButtonIcon icon={X} />
+          <ButtonIcon icon={X} size="sm" />
         </Button>
       </View>