patch 8.0.0912: cannot run a job in a hidden terminal

Problem:    Cannot run a job in a hidden terminal.
Solution:   Add option "hidden" and ++hidden.
diff --git a/src/version.c b/src/version.c
index 2972730..2d16a64 100644
--- a/src/version.c
+++ b/src/version.c
@@ -770,6 +770,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    912,
+/**/
     911,
 /**/
     910,