Fix ability for non project member to subscribe to an issue

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app/assets/javascripts/sidebar/components/subscriptions/sidebar_subscriptions_widget.vue

@@ -104,6 +104,9 @@ export default {
     isLoggedIn() {
       return Boolean(gon.current_user_id);
     },
+    canSubscribe() {
+      return this.emailsDisabled || !this.isLoggedIn;
+    },
   },
   methods: {
     setSubscribed(subscribed) {
@@ -176,7 +179,7 @@ export default {
       <gl-toggle
         :value="subscribed"
         :is-loading="isLoading"
-        :disabled="emailsDisabled || !isLoggedIn"
+        :disabled="canSubscribe"
         class="hide-collapsed gl-ml-auto"
         data-testid="subscription-toggle"
         :label="$options.i18n.notifications"

spec/features/issues/user_toggles_subscription_spec.rb

@@ -13,7 +13,7 @@ RSpec.describe "User toggles subscription", :js do
       visit(project_issue_path(project, issue))
     end
 
-    it 'toggle does not display' do
+    it 'does not display the Notification toggle' do
       expect(page).not_to have_button('Notifications')
     end
   end