patch 9.0.1541: CI: sound dummy is disabled

Problem:    CI: sound dummy is disabled.
Solution:   Make sound dummy work again. (closes #12380)
diff --git a/src/version.c b/src/version.c
index e5f4afa..c917be5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1541,
+/**/
     1540,
 /**/
     1539,