Feat: Notes (Non-Linked Comments) (#52)

Adds support for notes. These are comments that are not linked to specific lines of code in the MR.

lua/gitlab/actions/summary.lua

@@ -29,9 +29,8 @@ end
 
 -- This function will PUT the new description to the Go server
 M.edit_description     = function(text)
-  local jsonTable = { description = text }
-  local json = vim.json.encode(jsonTable)
-  job.run_job("/mr/description", "PUT", json, function(data)
+  local body = { description = text }
+  job.run_job("/mr/description", "PUT", body, function(data)
     vim.notify(data.message, vim.log.levels.INFO)
     state.INFO.description = data.mr.description
   end)