rails に bootstrapのテンプレートを適用したら、レスポンシブ用のナビバーが閉じない

前提・実現したいこと

ruby on railsのwebアプリのトップページにテンプレートbootstrapを挿入適用したい

webpackerを使ってbootstrap,jquery,popper,fontawesomeなどを導入しました。
参考
https://youtu.be/bn9arlhfaX

その後にテンプレートを挿入しました。
参考
https://youtu.be/5e3enFye--U

デザインや動きは想像通りにいったものの、ナビのメニューがもう一度クリックしても閉じないことに気がつきました。これをもう一度押したら閉じるようにしたいです。

関係あるのか分かりませんが、そもそものダウンロードしたテンプレートのコンソールに以下のエラーメッセージが発生していて当然自分のサイト上にも引き継がれています

jquery.easing.min.js:1 Uncaught TypeError: Cannot read property 'swing' of undefined
    at jquery.easing.min.js:1
    at jquery.easing.min.js:1
    at jquery.easing.min.js:1

環境
Mac OS
ruby 2.6.3
rails 6.1.1
bootstrap 4.5.3

html
1<!-- app>views>layouts>applciation.html.erb -->
2<!DOCTYPE html>
3<html lang="en">
4  <head>
5    <title>Manegement_app</title>
6    <meta name="viewport" content="width=device-width,initial-scale=1 shrink-to-fit=no">
7    <%= csrf_meta_tags %>
8    <%= csp_meta_tag %>
9
10    <%= stylesheet_link_tag 'application', media: 'all', 'data-turbolinks-track': 'reload' %>
11    <%= stylesheet_pack_tag 'application', media: 'all', 'data-turbolinks-track': 'reload' %>
12    <%= javascript_pack_tag 'application', 'data-turbolinks-track': 'reload' %>
13
14    
15    <!-- Font Awesome icons (free version) -->
16    <script src="https://use.fontawesome.com/releases/v5.15.1/js/all.js" crossorigin="anonymous"></script>
17
18    
19    <link href="https://fonts.googleapis.com/css?family=Merriweather+Sans:400,700" rel="stylesheet" />
20    <link href="https://fonts.googleapis.com/css?family=Merriweather:400,300,300italic,400italic,700,700italic" rel="stylesheet" type="text/css" />
21
22    
23    <link href="https://cdnjs.cloudflare.com/ajax/libs/magnific-popup.js/1.1.0/magnific-popup.min.css" rel="stylesheet" />
24
25    
26    <link href="static_pages/css/styles.css" rel="stylesheet" />
27
28
29  </head>
30
31  <body id="page-top">
32
33
34    <%= render 'layouts/navbar' %>
35
36    <%= yield %>
37
38
39    <footer class="bg-light py-5">
40      <div class="container"><div class="small text-center text-muted">Copyright © 2021 - Koudai Akiwa</div></div>
41      <!--<div class="container"><div class="small text-center text-muted">Copyright © 2020 - Start Bootstrap</div></div>-->
42    </footer>
43      
44      
45      <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js"></script>
46      <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-easing/1.4.1/jquery.easing.min.js"></script>
47      <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js"></script>
48      <script src="https://cdnjs.cloudflare.com/ajax/libs/magnific-popup.js/1.1.0/jquery.magnific-popup.min.js"></script>
49      
50     
51
52      <script src="static_pages/js/scripts.js"></script>
53   
54
55  </body>
56  
57  
58
59
60
61
62
63</html>
64
65

<!-- app>views>layouts>_navbar.html.erb -->
<!-- Navigation-->
<nav class="navbar navbar-expand-lg navbar-light fixed-top py-3" id="mainNav">
    <div class="container">
        <a class="navbar-brand js-scroll-trigger" href="#page-top">Manegement App</a> <!--title変更-->
        <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarResponsive" aria-controls="navbarResponsive" aria-expanded="false" aria-label="Toggle navigation"><span class="navbar-toggler-icon"></span></button>
        <div class="collapse navbar-collapse" id="navbarResponsive">
            <ul class="navbar-nav ml-auto my-2 my-lg-0">
                <li class="nav-item"><a class="nav-link js-scroll-trigger" href="#about">About</a></li>
                <li class="nav-item"><a class="nav-link js-scroll-trigger" href="#services">Services</a></li>
                <!--<li class="nav-item"><a class="nav-link js-scroll-trigger" href="#portfolio">Price</a></li>-->
                <li class="nav-item"><a class="nav-link js-scroll-trigger" href="#contact">Contact</a></li>
            </ul>
        </div>
    </div>
</nav>

Javascript
1/*!
2    * app>static_pages>js>script.js
3    * Start Bootstrap - Creative v6.0.4 (https://startbootstrap.com/theme/creative)
4    * Copyright 2013-2020 Start Bootstrap
5    * Licensed under MIT (https://github.com/StartBootstrap/startbootstrap-creative/blob/master/LICENSE)
6    */
7    (function($) {
8  "use strict"; // Start of use strict
9
10  // Smooth scrolling using jQuery easing
11  $('a.js-scroll-trigger[href*="#"]:not([href="#"])').click(function() {
12    if (location.pathname.replace(/^//, '') == this.pathname.replace(/^//, '') && location.hostname == this.hostname) {
13      var target = $(this.hash);
14      target = target.length ? target : $('[name=' + this.hash.slice(1) + ']');
15      if (target.length) {
16        $('html, body').animate({
17          scrollTop: (target.offset().top - 72)
18        }, 1000, "easeInOutExpo");
19        return false;
20      }
21    }
22  });
23
24  // Closes responsive menu when a scroll trigger link is clicked
25  $('.js-scroll-trigger').click(function() {
26    $('.navbar-collapse').collapse('hide');
27  });
28
29  // Activate scrollspy to add active class to navbar items on scroll
30  $('body').scrollspy({
31    target: '#mainNav',
32    offset: 75
33  });
34
35  // Collapse Navbar
36  var navbarCollapse = function() {
37    if ($("#mainNav").offset().top > 100) {
38      $("#mainNav").addClass("navbar-scrolled");
39    } else {
40      $("#mainNav").removeClass("navbar-scrolled");
41    }
42  };
43
44  
45  // Collapse now if page is not at top
46  navbarCollapse();
47  // Collapse the navbar when page is scrolled
48  $(window).scroll(navbarCollapse);
49
50  // Magnific popup calls
51  $('#portfolio').magnificPopup({
52    delegate: 'a',
53    type: 'image',
54    tLoading: 'Loading image #%curr%...',
55    mainClass: 'mfp-img-mobile',
56    gallery: {
57      enabled: true,
58      navigateByImgClick: true,
59      preload: [0, 1]
60    },
61    image: {
62      tError: '<a href="%url%">The image #%curr%</a> could not be loaded.'
63    }
64  });
65
66})(jQuery); // End of use strict
67

javascript
1//app>javascript>packs>application.js
2import Rails from "@rails/ujs"
3import Turbolinks from "turbolinks"
4import * as ActiveStorage from "@rails/activestorage"
5import "channels"
6
7Rails.start()
8Turbolinks.start()
9ActiveStorage.start()
10
11import 'bootstrap'
12import '../stylesheets/application'
13import '@fortawesome/fontawesome-free/js/all'
14
15
16