Update the "getRepositoriesByCountry"-endpoint to return up to 10_000 repositories.

src/main/java/eu/dnetlib/repo/manager/service/RepositoryServiceImpl.java

@@ -228,7 +228,7 @@ public class RepositoryServiceImpl implements RepositoryService {
                                                             Boolean managed) {
         logger.debug("Getting repositories by country!");
         int page = 0;
-        int size = 100;
+        int size = 10_000;   // Include all repositories. Some countries have more than a thousand.
 
         String filterKey = "UNKNOWN";
         if (mode.equalsIgnoreCase("repository"))