fix(route/sciencedirect): fix that abstract will not show when highlights appear (#20333)

* fix(route/sciencedirect): fix abstract will not show when highlights appear

now both abstract and highlights will show. only abstract will be shown when there is no highlights for the paper

* Update current-issue.ts

* fix(route/sciencedirect): fix vary length of abstract array

lib/routes/sciencedirect/current-issue.ts

@@ -76,8 +76,14 @@ async function handler(ctx) {
                     },
                 });
 
-                item.description = response.data[0].abstracts[0].html ?? '';
-
+                const abstracts = response.data?.[0]?.abstracts ?? [];
+                item.description =
+                    abstracts.length === 0
+                        ? ''
+                        : abstracts
+                              .map((abs) => abs?.html ?? '')
+                              .filter(Boolean)
+                              .join('<br/><br/>');
                 return item;
             })
         )