handle NPE when calling GitlabGroup.getLdapAccess()

src/main/java/org/gitlab/api/models/GitlabGroup.java

@@ -49,6 +49,9 @@ public class GitlabGroup {
     }
 
     public GitlabAccessLevel getLdapAccess() {
+        if(ldapAccess == null) {
+            return null;
+        }
         return GitlabAccessLevel.fromAccessValue(ldapAccess);
     }
 

src/test/java/org/gitlab/api/models/GitlabGroupTest.java

@@ -13,4 +13,10 @@ public class GitlabGroupTest {
         group.setLdapAccess(null);
     }
 
+    @Test
+    public void getLdapAccessHandlesNull() {
+        GitlabGroup group = new GitlabGroup();
+        group.setLdapAccess(null);
+        group.getLdapAccess();
+    }
 }