Migrate to Bootstrap 5 (#918)

* Migrate to Bootstrap 5

* Fix dropdown

* Fix horizontal line color

* Fix vertical line

* Migrate bootstrap on example site

* Fix style issue + scroll spy

Signed-off-by: hossainemruz <hossainemruz@gmail.com>

---------

Signed-off-by: hossainemruz <hossainemruz@gmail.com>
Co-authored-by: Emruz Hossain <hossainemruz@gmail.com>

layouts/partials/footer.html

@@ -66,7 +66,7 @@
 
   <footer id="footer" class="container-fluid text-center align-content-center footer pb-2">
     <div class="container pt-5">
-      <div class="row text-left">
+      <div class="row text-start">
         {{ if $navigationEnabled }}
         <div class="col-md-4 col-sm-12">
           <h5>{{ i18n "navigation" }}</h5>
@@ -193,7 +193,7 @@
     {{ if $credentialsEnabled }}
     <hr />
     <div class="container">
-      <div class="row text-left">
+      <div class="row text-start">
         <div class="col-md-4">
           <a id="theme" href="https://github.com/hugo-toha/toha" target="_blank" rel="noopener">
             <img src="{{ $themeLogo }}" alt="Toha Theme Logo">
@@ -201,7 +201,7 @@
           </a>
         </div>
         <div class="col-md-4 text-center">{{ $copyrightNotice | markdownify }}</div>
-        <div class="col-md-4 text-right">
+        <div class="col-md-4 text-end">
           <a id="hugo" href="https://gohugo.io/" target="_blank" rel="noopener">{{ i18n "hugoAttributionText" }}
           <img
             src="{{ $hugoLogo }}"