patch 8.0.0453: adding fold marker creates new comment

Problem:    Adding fold marker creates new comment.
Solution:   Use an existing comment if possible. (LemonBoy, closes #1549)
diff --git a/src/version.c b/src/version.c
index 1574f9c..28c9294 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    453,
+/**/
     452,
 /**/
     451,