本番環境の非同期でのいいね機能の実装

前提・実現したいこと

プログラミング初学者です。現在オリジナルのアプリを制作しています。
https://qiita.com/fumikao/items/373caa60b77f27f2dbdd
こちらを参考に非同期でのいいね機能を実装しました。ローカル環境ではうまく動いたのですが、herokuで本番環境にデプロイすると、クリックしても動かない状態になります。解決方法教えていただけますでしょうか。

該当のソースコード

==============================app/view/layouts/application.html.erb===============================
<!DOCTYPE html>
<html>
  <head>
    <title>Viewhome</title>
    <%= csrf_meta_tags %>
    <%= csp_meta_tag %>

    <%= stylesheet_link_tag 'application', media: 'all', 'data-turbolinks-track': 'reload' %>
    <%= javascript_pack_tag 'application', 'data-turbolinks-track': 'reload' %>
    <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js" integrity="sha384-wHAiFfRlMFy6i5SRaxvfOCifBUQy1xHdJ/yoi7FRNXMRBu5WHdZYu1hA6ZOblgut" crossorigin="anonymous"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.2.1/js/bootstrap.min.js" integrity="sha384-B0UglyR+jN6CkvvICOB2joaf5I4l3gm9GU6Hc1og6Ls7i6U/mkkaduKaBhlAXv9k" crossorigin="anonymous"></script>
    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
    
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">
    <%= render 'layouts/shim' %>
  </head>

  <body>
    <%= render 'layouts/header' %>
    <div class="container">
      <% flash.each do |message_type, message| %>
        <div class="alert alert-<%= message_type %>"><%= message %></div>
      <% end %>
    </div>
    
    <%= yield %>
  </body>
</html>

================================app/javascript/packs/application.js============
// This file is automatically compiled by Webpack, along with any other files
// present in this directory. You're encouraged to place your actual application logic in
// a relevant structure within app/javascript and only use these pack files to reference
// that code so it'll be compiled.

require("@rails/ujs").start()
require("turbolinks").start()
require("@rails/activestorage").start()
require("channels")
require("jquery")


// Uncomment to copy all static images under ../images to the output folder and reference
// them with the image_pack_tag helper in views (e.g <%= image_pack_tag 'rails.png' %>)
// or the `imagePath` JavaScript helper below.
//
// const images = require.context('../images', true)
// const imagePath = (name) => images(name, true)


//= require jquery
//= require rails-ujs
//= require_tree .

===============================app/view/users/_like.html.erb=======================================
<% if Like.find_by(user_id: current_user.id, post_id: @post.id) %>
  <%= link_to "/posts/#{@post.id}/likes", method: :delete, remote: true do %>
    <span class="fa fa-heart like-btn-unlike"></span>
  <% end %>
<% else %> 
  <%= link_to "/posts/#{@post.id}/likes", method: :post, remote: true do %>
    <span class="fa fa-heart like-btn"></span>
  <% end %>
<% end %>
<%= @post.likes.length %>

=====================================like_controller.erb=====================================
class LikesController < ApplicationController
  before_action :logged_in_user
  before_action :set_post

  def create
    @like = Like.create(user_id: current_user.id,post_id: @post.id)
  end

  def destroy
    @like=Like.find_by(user_id: current_user.id, post_id: @post.id)
    @like.destroy
  end

  private
    def set_post
      @post = Post.find(params[:post_id])
    end
  
end

試したこと

https://qiita.com/avicii2314/items/1c51f506678c6a3e6bc3
こちらを参考に<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>をapp/view/layouts/application.html.erbに追加したのですが変化ありませんでした。