fix: 🐛 Linked Identities visa value separator

TODO: fill issue ID from JIRA or remove

closes PRX-???

src/main/java/cz/muni/ics/ga4gh/base/Utils.java

@@ -29,6 +29,7 @@ import java.util.Date;
 import lombok.NonNull;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.util.StringUtils;
+import org.yaml.snakeyaml.util.UriEncoder;
 
 @Slf4j
 public class Utils {
@@ -191,9 +192,7 @@ public class Utils {
     }
 
     public static String constructLinkedIdentity(String sub, String iss) {
-        return URLEncoder.encode(sub, StandardCharsets.UTF_8)
-            + ','
-            + URLEncoder.encode(iss, StandardCharsets.UTF_8);
+        return UriEncoder.encode(sub) + ',' + UriEncoder.encode(iss);
     }
 
 }