Fix: Keep empty lines in discussion tree (#173)

* Docs: Fix typos and remove trailing spaces

* Fix: Split strings by new lines correctly

* Docs: Recommend breakindent option to improve tree nodes indentation

* Fix: Replace whole buffer when creating a new suggestion

Previously, a trailing empty line was left in the buffer.

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Co-authored-by: Jakub Bortlík <jakub.bortlik@phonexia.com>

lua/gitlab/actions/discussions/tree.lua

@@ -92,7 +92,7 @@ end
 ---@return NuiTree.Node[]
 local function build_note_body(note, resolve_info)
   local text_nodes = {}
-  for bodyLine in note.body:gmatch("[^\n]+") do
+  for bodyLine in u.split_by_new_lines(note.body) do
     local line = attach_uuid(bodyLine)
     table.insert(
       text_nodes,