patch 8.0.0220: completion of highlight names misses a few values

Problem:    Completion for :match does not show "none" and other missing
            highlight names.
Solution:   Skip over cleared entries before checking the index to be at the
            end.
diff --git a/src/version.c b/src/version.c
index 90f056b..84cb940 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    220,
+/**/
     219,
 /**/
     218,