patch 8.1.1405: "highlight" option of popup windows not supported

Problem:    "highlight" option of popup windows not supported.
Solution:   Implement the "highlight" option.
diff --git a/src/version.c b/src/version.c
index 2b869f0..04de1af 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1405,
+/**/
     1404,
 /**/
     1403,