patch 8.1.1944: leaking memory when using sound callback

Problem:    Leaking memory when using sound callback.
Solution:   src/sound.c
diff --git a/src/version.c b/src/version.c
index 4f0018f..71901c9 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1944,
+/**/
     1943,
 /**/
     1942,