patch 8.0.1818: lines remove from wrong buffer when using terminal window

Problem:    Lines remove from wrong buffer when using terminal window.
Solution:   Make sure to use tl_buffer.
diff --git a/src/version.c b/src/version.c
index 81f867b..5d85a80 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1818,
+/**/
     1817,
 /**/
     1816,