patch 8.2.3586: command completion test fails

Problem:    Command completion test fails.
Solution:   Add new argument to expected output
diff --git a/src/testdir/test_usercommands.vim b/src/testdir/test_usercommands.vim
index 48bfd5a..6707a03 100644
--- a/src/testdir/test_usercommands.vim
+++ b/src/testdir/test_usercommands.vim
@@ -319,10 +319,10 @@
 
 func Test_CmdCompletion()
   call feedkeys(":com -\<C-A>\<C-B>\"\<CR>", 'tx')
-  call assert_equal('"com -addr bang bar buffer complete count nargs range register', @:)
+  call assert_equal('"com -addr bang bar buffer complete count keepscript nargs range register', @:)
 
   call feedkeys(":com -nargs=0 -\<C-A>\<C-B>\"\<CR>", 'tx')
-  call assert_equal('"com -nargs=0 -addr bang bar buffer complete count nargs range register', @:)
+  call assert_equal('"com -nargs=0 -addr bang bar buffer complete count keepscript nargs range register', @:)
 
   call feedkeys(":com -nargs=\<C-A>\<C-B>\"\<CR>", 'tx')
   call assert_equal('"com -nargs=* + 0 1 ?', @:)