patch 8.2.3402: invalid memory access when using :retab with large value

Problem:    Invalid memory access when using :retab with large value.
Solution:   Check the number is positive.
diff --git a/src/version.c b/src/version.c
index 8f502cc..a5e931c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -756,6 +756,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3402,
+/**/
     3401,
 /**/
     3400,