patch 8.2.5078: substitute test has a one second delay

Problem:    Substitute test has a one second delay.
Solution:   Use ":silent!".  Add another test case. (closes #10558)
diff --git a/src/version.c b/src/version.c
index f5c0fd7..aec6f4b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -735,6 +735,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    5078,
+/**/
     5077,
 /**/
     5076,