vim-patch:9.1.1331: Leaking memory with cmdcomplete()

Problem:  Leaking memory with cmdcomplete()
          (zeertzjq, after v9.1.1329)
Solution: free the memory (Girish Palya)

closes: vim/vim#17190

5c3d1e3258

Co-authored-by: Girish Palya <girishji@gmail.com>

src/nvim/eval.lua

@@ -1279,7 +1279,7 @@ M.funcs = {
     name = 'cmdcomplete_info',
     params = {},
     returns = 'table<string,any>',
-    signature = 'cmdcomplete_info([{what}])',
+    signature = 'cmdcomplete_info()',
   },
   col = {
     args = { 1, 2 },