fix: NaN library components are out of sync [FC-0083] (openedx#1864)

Author: pomegranited

src/course-libraries/OutOfSyncAlert.tsx

@@ -34,7 +34,7 @@ export const OutOfSyncAlert: React.FC<OutOfSyncAlertProps> = ({
 }) => {
   const intl = useIntl();
   const { data, isLoading } = useEntityLinksSummaryByDownstreamContext(courseId);
-  const outOfSyncCount = data?.reduce((count, lib) => count + lib.readyToSyncCount, 0);
+  const outOfSyncCount = data?.reduce((count, lib) => count + (lib.readyToSyncCount || 0), 0);
   const alertKey = `outOfSyncCountAlert-${courseId}`;
 
   useEffect(() => {

src/course-libraries/__mocks__/linkCourseSummary.json

@@ -14,7 +14,6 @@
   {
     "upstreamContextTitle": "CS problems",
     "upstreamContextKey": "lib:OpenedX:CSPROB",
-    "readyToSyncCount": 0,
     "totalCount": 3
   }
 ]