patch 9.0.0718: extra empty line between two virtual text "below"

Problem:    Extra empty line between two virtual text "below" when 'wrap' and
            'number' are set.
Solution:   Reset "before" when there is no text in the screen line.
            (closes #11334)
diff --git a/src/version.c b/src/version.c
index f33673e..ac3b567 100644
--- a/src/version.c
+++ b/src/version.c
@@ -700,6 +700,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    718,
+/**/
     717,
 /**/
     716,