fix auth tests

auth/sessions_test.go

@@ -53,12 +53,11 @@ func TestSessionExpiry(t *testing.T) {
 	}
 
 	s1 := &Session{Username: "test"}
-	id, err := sm.insertNew(s1)
-	if err != nil {
+	if err = sm.insert(s1); err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
 
-	s2 := sm.get(id)
+	s2 := sm.get(s1.ID)
 	if s2 == nil {
 		t.Fatalf("session-manager returned no session")
 	}