add template api folder filters

app/controllers/api/templates_controller.rb

@@ -9,6 +9,7 @@ module Api
 
       templates = params[:archived] ? templates.archived : templates.active
       templates = templates.where(application_key: params[:application_key]) if params[:application_key].present?
+      templates = templates.joins(:folder).where(folder: { name: params[:folder] }) if params[:folder].present?
 
       templates = paginate(templates.preload(:author, documents_attachments: :blob))