patch 8.0.1814: crash with terminal window and with 'lazyredraw' set

Problem:    Crash with terminal window and with 'lazyredraw' set. (Antoine)
Solution:   Check the terminal still exists after update_screen().
diff --git a/src/version.c b/src/version.c
index 966463a..918e192 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1814,
+/**/
     1813,
 /**/
     1812,