`-Ex` mode job stdtout is empty on vim 7.4.1689
```
 ~/.vims/741689/bin/vim -Nu test/vimrc -c 'Vader! test/api/job.vader'
Vader note: cannot print to stderr reliably/directly.  Please consider using Vim's -es/-Es option (mode=n).
VIM - Vi IMproved 7.4 (2013 Aug 10, compiled Apr  9 2022 10:59:43)
Included patches: 1-1689
Compiled by wsdjeg
Huge version without GUI.  Features included (+) or not (-):
+acl             +conceal         +file_in_path    +linebreak       -mouse_sysmouse  -python3         -tcl             +wildmenu
+arabic          +cryptv          +find_in_path    +lispindent      +mouse_urxvt     +quickfix        +terminfo        +windows
+autocmd         +cscope          +float           +listcmds        +mouse_xterm     +reltime         +termresponse    +writebackup
-balloon_eval    +cursorbind      +folding         +localmap        +multi_byte      +rightleft       +textobjects     -X11
-browse          +cursorshape     -footer          -lua             +multi_lang      -ruby            +timers          -xfontset
++builtin_terms  +dialog_con      +fork()          +menu            -mzscheme        +scrollbind      +title           -xim
+byte_offset     +diff            +gettext         +mksession       +netbeans_intg   +signs           -toolbar         -xsmp
+channel         +digraphs        -hangul_input    +modify_fname    +packages        +smartindent     +user_commands   -xterm_clipboard
+cindent         -dnd             +iconv           +mouse           +path_extra      +startuptime     +vertsplit       -xterm_save
-clientserver    -ebcdic          +insert_expand   -mouseshape      -perl            +statusline      +virtualedit     -xpm
-clipboard       +emacs_tags      +job             +mouse_dec       +persistent_undo -sun_workshop    +visual
+cmdline_compl   +eval            +jumplist        -mouse_gpm       +postscript      +syntax          +visualextra
+cmdline_hist    +ex_extra        +keymap          -mouse_jsbterm   +printer         +tag_binary      +viminfo
+cmdline_info    +extra_search    +langmap         +mouse_netterm   +profile         +tag_old_static  +vreplace
+comments        +farsi           +libcall         +mouse_sgr       -python          -tag_any_white   +wildignore
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
 2nd user vimrc file: "~/.vim/vimrc"
      user exrc file: "$HOME/.exrc"
  fall-back for $VIM: "/home/wsdjeg/.vims/741689/share/vim"
Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H     -g -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
Linking: gcc   -L/usr/local/lib -Wl,--as-needed -o vim        -lm -ltinfo -lnsl  -ldl

Starting Vader: 1 suite(s), 1 case(s)
  Starting Vader: /home/wsdjeg/.SpaceVim/test/api/job.vader
    (1/1) [EXECUTE]  SpaceVim api: job
      > cat (GNU coreutils) 8.28
      > Copyright (C) 2017 Free Software Foundation, Inc.
      > License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
      > This is free software: you are free to change and redistribute it.
      > There is NO WARRANTY, to the extent permitted by law.
      >
      > Written by Torbjorn Granlund and Richard M. Stallman.
  Success/Total: 1/1
Success/Total: 1/1 (assertions: 3/3)
Elapsed time: 2.03 sec.
```

```
~/.vims/741689/bin/vim -Nu test/vimrc -Es -c 'Vader! test/api/job.vader'
VIM - Vi IMproved 7.4 (2013 Aug 10, compiled Apr  9 2022 10:59:43)
Included patches: 1-1689
Compiled by wsdjeg
Huge version without GUI.  Features included (+) or not (-):
+acl             +conceal         +file_in_path    +linebreak       -mouse_sysmouse  -python3         -tcl             +wildmenu
+arabic          +cryptv          +find_in_path    +lispindent      +mouse_urxvt     +quickfix        +terminfo        +windows
+autocmd         +cscope          +float           +listcmds        +mouse_xterm     +reltime         +termresponse    +writebackup
-balloon_eval    +cursorbind      +folding         +localmap        +multi_byte      +rightleft       +textobjects     -X11
-browse          +cursorshape     -footer          -lua             +multi_lang      -ruby            +timers          -xfontset
++builtin_terms  +dialog_con      +fork()          +menu            -mzscheme        +scrollbind      +title           -xim
+byte_offset     +diff            +gettext         +mksession       +netbeans_intg   +signs           -toolbar         -xsmp
+channel         +digraphs        -hangul_input    +modify_fname    +packages        +smartindent     +user_commands   -xterm_clipboard
+cindent         -dnd             +iconv           +mouse           +path_extra      +startuptime     +vertsplit       -xterm_save
-clientserver    -ebcdic          +insert_expand   -mouseshape      -perl            +statusline      +virtualedit     -xpm
-clipboard       +emacs_tags      +job             +mouse_dec       +persistent_undo -sun_workshop    +visual
+cmdline_compl   +eval            +jumplist        -mouse_gpm       +postscript      +syntax          +visualextra
+cmdline_hist    +ex_extra        +keymap          -mouse_jsbterm   +printer         +tag_binary      +viminfo
+cmdline_info    +extra_search    +langmap         +mouse_netterm   +profile         +tag_old_static  +vreplace
+comments        +farsi           +libcall         +mouse_sgr       -python          -tag_any_white   +wildignore
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
 2nd user vimrc file: "~/.vim/vimrc"
      user exrc file: "$HOME/.exrc"
  fall-back for $VIM: "/home/wsdjeg/.vims/741689/share/vim"
Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H     -g -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
Linking: gcc   -L/usr/local/lib -Wl,--as-needed -o vim        -lm -ltinfo -lnsl  -ldl

Starting Vader: 1 suite(s), 1 case(s)
  Starting Vader: /home/wsdjeg/.SpaceVim/test/api/job.vader
    (1/1) [EXECUTE]  SpaceVim api: job
      > cat (GNU coreutils) 8.28
      > Copyright (C) 2017 Free Software Foundation, Inc.
      > License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
      > This is free software: you are free to change and redistribute it.
      > There is NO WARRANTY, to the extent permitted by law.
      >
      > Written by Torbjorn Granlund and Richard M. Stallman.
    (1/1) [EXECUTE] (X) 'foo' should be equal to ''
  Success/Total: 0/1
Success/Total: 0/1 (assertions: 0/1)
Elapsed time: 2.05 sec.
```