patch 8.2.0039: memory access error when "z=" has no suggestions

Problem:    Memory access error when "z=" has no suggestions.
Solution:   Check for negative index.
diff --git a/src/version.c b/src/version.c
index e6f0cf0..9f7f48a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    39,
+/**/
     38,
 /**/
     37,