patch 8.0.0869: job output is sometimes not displayed in a terminal

Problem:    Job output is sometimes not displayed in a terminal.
Solution:   Flush output before closing the channel.
diff --git a/src/version.c b/src/version.c
index a721d42..d1b20b1 100644
--- a/src/version.c
+++ b/src/version.c
@@ -770,6 +770,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    869,
+/**/
     868,
 /**/
     867,