fix: don't update suggestion buffer if the text doesn't change

This prevents the folding in the suggestion buffer to get off when the
suggestion doesn't actually modify the original and the user types some
text outside of the tripple-quoted suggestion segment.

Author: jakubbortlik

lua/gitlab/actions/suggestions.lua

@@ -527,7 +527,12 @@ local create_autocommands = function(
     local suggestion = List.new(suggestions):find(function(sug)
       return current_line <= sug.note_end_linenr
     end)
-    if not suggestion or suggestion == last_suggestion then
+    local old_buffer_text = u.get_buffer_text(suggestion_buf)
+    if
+      not suggestion
+      or suggestion == last_suggestion
+      or old_buffer_text == table.concat(suggestion.full_text, "\n")
+    then
       return
     end
     set_buffer_lines(suggestion_buf, suggestion.full_text, imply_local)