gdiplus/tests: Fix matrix leak (Valgrind).

Signed-off-by: Nikolay Sivov <nsivov@codeweavers.com>
Signed-off-by: Vincent Povirk <vincent@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
diff --git a/dlls/gdiplus/tests/matrix.c b/dlls/gdiplus/tests/matrix.c
index 3e655ce..5ca0209 100644
--- a/dlls/gdiplus/tests/matrix.c
+++ b/dlls/gdiplus/tests/matrix.c
@@ -164,6 +164,7 @@
     GdipCreateMatrix2(2.0/16.0, 2.0/16.0, -5.0/16.0, 3.0/16.0, 3.0/16.0, -21.0/16.0, &inverted);
     GdipIsMatrixEqual(matrix, inverted, &equal);
     expect(TRUE, equal);
+    GdipDeleteMatrix(matrix);
 
     GdipCreateMatrix2(0.0006, 0, 0, 0.0006, 400, 400, &matrix);
     status = GdipInvertMatrix(matrix);