patch 8.2.4122: ":command Cmd" does not show custom completion argument

Problem:    ":command Cmd" does not show custom completion argument.
Solution:   Show the completion argument when using ":verbose".
diff --git a/src/version.c b/src/version.c
index bc75522..bee41fd 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4122,
+/**/
     4121,
 /**/
     4120,