patch 8.2.0432: a few tests fail in a huge terminal

Problem:    A few tests fail in a huge terminal.
Solution:   Make the tests pass. (Dominique Pelle, closes #5829)
diff --git a/src/testdir/test_window_cmd.vim b/src/testdir/test_window_cmd.vim
index 1a67666..040324d 100644
--- a/src/testdir/test_window_cmd.vim
+++ b/src/testdir/test_window_cmd.vim
@@ -1013,13 +1013,13 @@
   let dir = (a:dir_arg == 'v') ? 'vert ' : ''
 
   " Open as many windows as possible
-  for i in range(500)
+  while v:true
     try
       exe dir . 'new'
     catch /E36:/
       break
     endtry
-  endfor
+  endwhile
 
   call writefile(['first', 'second', 'third'], 'Xfile1')
   call writefile([], 'Xfile2')