patch 8.2.1326: Vim9: skipping over white space after list

Problem:    Vim9: skipping over white space after list.
Solution:   Do not skip white space, a following [] would be misinterpreted.
            (closes #6552)  Fix a few side effects.
diff --git a/src/testdir/test_gn.vim b/src/testdir/test_gn.vim
index c72da92..b90aa5f 100644
--- a/src/testdir/test_gn.vim
+++ b/src/testdir/test_gn.vim
@@ -120,7 +120,7 @@
   sil! %d_
 
   " search using the \zs atom
-  call setline(1, [' nnoremap', '' , 'nnoremap'])
+  call setline(1, [' nnoremap', '', 'nnoremap'])
   set wrapscan&vim
   let @/ = '\_s\zsnnoremap'
   $