patch 8.2.0678: rare crash for popup menu

Problem:    Rare crash for popup menu.
Solution:   Check for NULL pointer. (Nobuhiro Takasaki, closes #6027)
diff --git a/src/version.c b/src/version.c
index 8f1539a..29763f7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -747,6 +747,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    678,
+/**/
     677,
 /**/
     676,