Load jquery without importmap.

Fixes rails/jquery-rails#291

Author: kidhab

Diff for: app/javascript/application_legacy.js

@@ -0,0 +1 @@
+//= require jquery

Diff for: app/views/layouts/application.haml

@@ -6,6 +6,7 @@
     = stylesheet_link_tag 'application'
     = csrf_meta_tag
     = javascript_importmap_tags
+    = javascript_include_tag "application_legacy"
   %body
     %nav{:class => "navbar navbar-expand-lg navbar-light bg-light"}
       .container-fluid

Diff for: config/initializers/assets.rb

@@ -11,4 +11,4 @@
 # Precompile additional assets.
 # application.js, application.css, and all non-JS/CSS in the app/assets
 # folder are already added.
-# Rails.application.config.assets.precompile += %w( admin.js admin.css )
+Rails.application.config.assets.precompile += %w( application_legacy.js bootstrap.min.js popper.js )