patch 8.1.0180: static analysis errors in Lua interface

Problem:    Static analysis errors in Lua interface. (Coverity)
Solution:   Check for NULL pointers.
diff --git a/src/version.c b/src/version.c
index 1dae71f..7275901 100644
--- a/src/version.c
+++ b/src/version.c
@@ -790,6 +790,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    180,
+/**/
     179,
 /**/
     178,