no more sonar blockers

src/main/java/org/hbp/mip/controllers/ArticlesApi.java

@@ -134,7 +134,7 @@ public class ArticlesApi {
             } catch (IOException e) {
                 e.printStackTrace();
             }
-            String slug = slg != null ? slg.slugify(article.getTitle()) : null;
+            String slug = slg != null ? slg.slugify(article.getTitle()) : "";
 
             i = 0;
             do {

src/main/java/org/hbp/mip/controllers/ModelsApi.java

@@ -161,12 +161,13 @@ public class ModelsApi {
             } while(count > 0);
 
             Slugify slg = null;
+            String slug = "";
             try {
                 slg = new Slugify();
+                slug = slg.slugify(model.getTitle());
             } catch (IOException e) {
                 e.printStackTrace();
             }
-            String slug = slg != null ? slg.slugify(model.getTitle()) : null;
 
             i = 0;
             do {