Change User Roles (#1153)

* Modify user service and controller

* Modify Template

* Add messages

* Fix Username output

* Add tooltip

* Change Role Modify logic

* Add Roles from database to existing users

* Add default select Fillers

* Indent JS

* Add Change Role Related Translations

* Remove unnecessary Whitespace and imports

src/main/java/stirling/software/SPDF/repository/AuthorityRepository.java

@@ -9,4 +9,7 @@ import stirling.software.SPDF.model.Authority;
 public interface AuthorityRepository extends JpaRepository<Authority, Long> {
     // Set<Authority> findByUsername(String username);
     Set<Authority> findByUser_Username(String username);
+
+    Authority findByUserId(long user_id);
+
 }