fix(#2495): skip API action if node == nil (#2499)

* fix(#2495): skip action if node == nil

* simplify

---------

Co-authored-by: Alexander Courtis <alex@courtis.org>

lua/nvim-tree/api.lua

@@ -45,9 +45,11 @@ end
 local function wrap_node(f)
   return function(node, ...)
     node = node or require("nvim-tree.lib").get_node_at_cursor()
+    if node then
       f(node, ...)
     end
   end
+end
 
 ---@class ApiTreeOpenOpts
 ---@field path string|nil path