patch 8.0.0672: third item of synconcealed() changes too often

Problem:    Third item of synconcealed() changes too often. (Dominique Pelle)
Solution:   Reset the sequence number at the start of each line.
diff --git a/src/version.c b/src/version.c
index 9b2b048..d15b7db 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    672,
+/**/
     671,
 /**/
     670,