Tidy up authorization of organisations controller

- We already have a method to authenticate the scope of the user, so we can reuse that.

app/controllers/organisations_controller.rb

@@ -6,8 +6,8 @@ class OrganisationsController < ApplicationController
   before_action :authenticate_user!
   before_action :find_resource, except: %i[index new create]
   before_action :authenticate_scope!, except: [:index]
-  before_action { session_filters(specific_org: true) if support_user? }
-  before_action :set_session_filters, if: :support_user?
+  before_action -> { session_filters(specific_org: true) }, if: -> { current_user.support? }
+  before_action :set_session_filters, if: -> { current_user.support? }
 
   def index
     redirect_to organisation_path(current_user.organisation) unless current_user.support?
@@ -90,7 +90,6 @@ class OrganisationsController < ApplicationController
   end
 
   def logs
-    if current_user.support?
     organisation_logs = LettingsLog.all.where(owning_organisation_id: @organisation.id)
     unpaginated_filtered_logs = filtered_lettings_logs(organisation_logs, search_term, @session_filters)
 
@@ -103,20 +102,13 @@ class OrganisationsController < ApplicationController
         render "logs", layout: "application"
       end
     end
-    else
-      redirect_to(lettings_logs_path)
-    end
   end
 
   def download_csv
-    if current_user.support?
     organisation_logs = LettingsLog.all.where(owning_organisation_id: @organisation.id)
     unpaginated_filtered_logs = filtered_lettings_logs(organisation_logs, search_term, @session_filters)
 
     render "lettings_logs/download_csv", locals: { search_term:, count: unpaginated_filtered_logs.size, post_path: logs_email_csv_organisation_path }
-    else
-      redirect_to(download_csv_lettings_logs_path)
-    end
   end
 
   def email_csv
@@ -135,7 +127,7 @@ private
   end
 
   def authenticate_scope!
-    if %w[create new].include? action_name
+    if %w[create new logs download_csv].include? action_name
       head :unauthorized and return unless current_user.support?
     elsif current_user.organisation != @organisation && !current_user.support?
       render_not_found
@@ -145,8 +137,4 @@ private
   def find_resource
     @organisation = Organisation.find(params[:id])
   end
-
-  def support_user?
-    current_user.support?
-  end
 end