Use SimpleGrantedAuthority instead of deprecated GrantedAuthorityImpl

src/main/java/de/thm/arsnova/CasUserDetailsService.java

@@ -24,19 +24,18 @@ import java.util.List;
 import org.jasig.cas.client.validation.Assertion;
 import org.springframework.security.cas.userdetails.AbstractCasAssertionUserDetailsService;
 import org.springframework.security.core.GrantedAuthority;
-import org.springframework.security.core.authority.GrantedAuthorityImpl;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
 import org.springframework.security.core.userdetails.User;
 import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.stereotype.Service;
 
 @Service
-public class CasUserDetailsService extends
-		AbstractCasAssertionUserDetailsService {
+public class CasUserDetailsService extends AbstractCasAssertionUserDetailsService {
 
 	@Override
 	protected final UserDetails loadUserDetails(final Assertion assertion) {
 		final List<GrantedAuthority> grantedAuthorities = new ArrayList<GrantedAuthority>();
-		grantedAuthorities.add(new GrantedAuthorityImpl("ROLE_USER"));
+		grantedAuthorities.add(new SimpleGrantedAuthority("ROLE_USER"));
 
 		return new User(
 				assertion.getPrincipal().getName(),
@@ -46,6 +45,6 @@ public class CasUserDetailsService extends
 				true,
 				true,
 				grantedAuthorities
-		);
+				);
 	}
 }