patch 8.1.0944: format of nbdbg() arguments is not checked

Problem:    Format of nbdbg() arguments is not checked.
Solution:   Add format attribute.  Fix reported problems. (Dominique Pelle,
            closes #3992)
diff --git a/src/version.c b/src/version.c
index a59e185..b3244c1 100644
--- a/src/version.c
+++ b/src/version.c
@@ -780,6 +780,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    944,
+/**/
     943,
 /**/
     942,