[pygobject] Fix a couple of memory leaks in the tests

[Patrick Griffis <pgriffis src gnome org>]

commit 945d91245503c50c2137132b5e9ab2277065eae7
Author: David King <amigadave amigadave com>
Date:   Wed Jul 14 10:37:16 2021 +0100

    Fix a couple of memory leaks in the tests
    
    Found by Coverity.
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1938851

 tests/testhelpermodule.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/tests/testhelpermodule.c b/tests/testhelpermodule.c
index e6f6ffe4..eb17af87 100644
--- a/tests/testhelpermodule.c
+++ b/tests/testhelpermodule.c
@@ -362,11 +362,12 @@ test_paramspec_callback (GObject *object)
 static GValue *
 test_gvalue_callback (GObject *object, const GValue *v)
 {
-  GValue *ret = g_malloc0 (sizeof (GValue));
+  GValue *ret;
 
   g_return_val_if_fail (G_IS_OBJECT (object), NULL);
   g_return_val_if_fail (G_IS_VALUE (v), NULL);
 
+  ret = g_malloc0 (sizeof (GValue));
   g_value_init (ret, G_VALUE_TYPE (v));
   g_value_copy (v, ret);
   return ret;
@@ -375,10 +376,11 @@ test_gvalue_callback (GObject *object, const GValue *v)
 static GValue *
 test_gvalue_ret_callback (GObject *object, GType type)
 {
-  GValue *ret = g_malloc0 (sizeof (GValue));
+  GValue *ret;
 
   g_return_val_if_fail (G_IS_OBJECT (object), NULL);
 
+  ret = g_malloc0 (sizeof (GValue));
   g_value_init (ret, type);
 
   switch (type) {