patch 8.2.3647: GTK: when using ligatures the cursor is drawn wrong

Problem:    GTK: when using ligatures the cursor is drawn wrong.
Solution:   Clear more characters when ligatures are used. (Dusan Popovic,
            closes #9190)
diff --git a/src/version.c b/src/version.c
index c76ce02..1871c7f 100644
--- a/src/version.c
+++ b/src/version.c
@@ -758,6 +758,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3647,
+/**/
     3646,
 /**/
     3645,