fix: avoid E490 when using move_subtree_up and move_subtree_down (#1013)

* fix: set cursor using correct coordinates

The column coordinate of the cursor is given by
vim.fn.getcurpos()[3], and not vim.fin.getcurpos()[2].

* fix: add condition to avoid E490

In some cases, executing org-subtree-up-or-down would causes E490 No
fold found error when the functional calls vim.cmd([[norm!zc]]).
This extra condition gurantees this error won't be thrown.

---------

Co-authored-by: Kristijan Husak <husakkristijan@gmail.com>

Author: MarkSverdlov

lua/orgmode/org/mappings.lua

@@ -813,8 +813,8 @@ function OrgMappings:move_subtree_up()
   local foldclosed = vim.fn.foldclosed('.')
   vim.cmd(string.format(':%d,%dmove %d', range.start_line, range.end_line, target_line))
   local pos = vim.fn.getcurpos()
-  vim.fn.cursor(target_line + 1, pos[2])
-  if foldclosed > -1 and vim.fn.foldclosed('.') == -1 then
+  vim.fn.cursor(target_line + 1, pos[3])
+  if foldclosed > -1 and vim.fn.foldlevel('.') > 0 and vim.fn.foldclosed('.') == -1 then
     vim.cmd([[norm!zc]])
   end
 end
@@ -830,8 +830,8 @@ function OrgMappings:move_subtree_down()
   local foldclosed = vim.fn.foldclosed('.')
   vim.cmd(string.format(':%d,%dmove %d', range.start_line, range.end_line, target_line))
   local pos = vim.fn.getcurpos()
-  vim.fn.cursor(target_line + range.start_line - range.end_line, pos[2])
-  if foldclosed > -1 and vim.fn.foldclosed('.') == -1 then
+  vim.fn.cursor(target_line + range.start_line - range.end_line, pos[3])
+  if foldclosed > -1 and vim.fn.foldlevel('.') > 0 and vim.fn.foldclosed('.') == -1 then
     vim.cmd([[norm!zc]])
   end
 end