vim-patch:9.2.0413: Scrolling wrong with 'splitkeep' when changing 'cmdheight' (#39493)

Problem:  Cursor is not adjusted when 'cmdheight' is changed to cover
          the cursor with 'splitkeep' ~= "cursor".
Solution: Handle window resize for 'splitkeep' after changing 'cmdheight'.
          Ensure previous window height is set when changing 'splitkeep'
          (Luuk van Baal).

closes: vim/vim#20043

bd0f3e6da5

Co-authored-by: Luuk van Baal <luukvbaal@gmail.com>

src/nvim/options.lua

@@ -8633,6 +8633,7 @@ local options = {
     },
     {
       abbreviation = 'spk',
+      cb = 'did_set_splitkeep',
       defaults = 'cursor',
       values = { 'cursor', 'screen', 'topline' },
       desc = [=[